mac80211: don't compare TKIP TX MIC key in reinstall prevention

[pandora-kernel.git] / net / mac80211 / key.c

diff --git a/net/mac80211/key.c b/net/mac80211/key.c
index f2bdd6f..01c64f4 100644 (file)
--- a/net/mac80211/key.c
+++ b/net/mac80211/key.c
@@ -444,6 +444,39 @@ static void __ieee80211_key_destroy(struct ieee80211_key *key)
        kfree(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 !memcmp(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)
@@ -497,8 +530,7 @@ int ieee80211_key_link(struct ieee80211_key *key,
         * Silently accept key re-installation without really installing the
         * new version of the key to avoid nonce reuse or replay issues.
         */
-       if (old_key && key->conf.keylen == old_key->conf.keylen &&
-           !memcmp(key->conf.key, old_key->conf.key, key->conf.keylen)) {
+       if (ieee80211_key_identical(sdata, old_key, key)) {
                __ieee80211_key_free(key);
                ret = 0;
                goto out;