mac80211: 802.11w - CCMP for management frames

Extend CCMP to support encryption and decryption of unicast management
frames.

Signed-off-by: Jouni Malinen <j@w1.fi>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 22 insertions, 1 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index cd6bc87eec73..50c6c4fabea5 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -330,6 +330,22 @@ ieee80211_tx_h_multicast_ps_buf(struct ieee80211_tx_data *tx)
         return TX_CONTINUE;
 }
 
+static int ieee80211_use_mfp(__le16 fc, struct sta_info *sta,
+                             struct sk_buff *skb)
+{
+        if (!ieee80211_is_mgmt(fc))
+                return 0;
+
+        if (sta == NULL || !test_sta_flags(sta, WLAN_STA_MFP))
+                return 0;
+
+        if (!ieee80211_is_robust_mgmt_frame((struct ieee80211_hdr *)
+                                            skb->data))
+                return 0;
+
+        return 1;
+}
+
 static ieee80211_tx_result
 ieee80211_tx_h_unicast_ps_buf(struct ieee80211_tx_data *tx)
 {
@@ -428,10 +444,15 @@ ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
                         if (ieee80211_is_auth(hdr->frame_control))
                                 break;
                 case ALG_TKIP:
-                case ALG_CCMP:
                         if (!ieee80211_is_data_present(hdr->frame_control))
                                 tx->key = NULL;
                         break;
+                case ALG_CCMP:
+                        if (!ieee80211_is_data_present(hdr->frame_control) &&
+                            !ieee80211_use_mfp(hdr->frame_control, tx->sta,
+                                               tx->skb))
+                                tx->key = NULL;
+                        break;
                 }
         }