mac80211: Add MIC space only for TX key option

Add a key flag to indicates that the device only needs
MIC space and not a real MIC.
In such cases, keep the MIC zeroed for ease of debug.

Signed-off-by: David Spinadel <david.spinadel@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 2ee4af25256db2955d9052ce6ecf6a66ec810f95..906e902230662562c97f03a7ccd37e6339747eba 100644 (file)
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1552,6 +1552,9 @@ struct wireless_dev *ieee80211_vif_to_wdev(struct ieee80211_vif *vif);
  * @IEEE80211_KEY_FLAG_RESERVE_TAILROOM: This flag should be set by the
  *     driver for a key to indicate that sufficient tailroom must always
  *     be reserved for ICV or MIC, even when HW encryption is enabled.
+ * @IEEE80211_KEY_FLAG_PUT_MIC_SPACE: This flag should be set by the driver for
+ *     a TKIP key if it only requires MIC space. Do not set together with
+ *     @IEEE80211_KEY_FLAG_GENERATE_MMIC on the same key.
  */
 enum ieee80211_key_flags {
        IEEE80211_KEY_FLAG_GENERATE_IV_MGMT     = BIT(0),
@@ -1562,6 +1565,7 @@ enum ieee80211_key_flags {
        IEEE80211_KEY_FLAG_PUT_IV_SPACE         = BIT(5),
        IEEE80211_KEY_FLAG_RX_MGMT              = BIT(6),
        IEEE80211_KEY_FLAG_RESERVE_TAILROOM     = BIT(7),
+       IEEE80211_KEY_FLAG_PUT_MIC_SPACE        = BIT(8),
 };
 
 /**
@@ -1593,8 +1597,8 @@ struct ieee80211_key_conf {
        u8 icv_len;
        u8 iv_len;
        u8 hw_key_idx;
-       u8 flags;
        s8 keyidx;
+       u16 flags;
        u8 keylen;
        u8 key[0];
 };

diff --git a/net/mac80211/key.c b/net/mac80211/key.c
index 938049395f9073169035ded5f506cb0c192c41f7..aee05ec3f7ea903bd4a4254c70529e7740092726 100644 (file)
--- a/net/mac80211/key.c
+++ b/net/mac80211/key.c
@@ -178,13 +178,17 @@ static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
        if (!ret) {
                key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
 
-               if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
+               if (!((key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
+                                          IEEE80211_KEY_FLAG_PUT_MIC_SPACE)) ||
                      (key->conf.flags & 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;
        }
 
@@ -237,7 +241,8 @@ static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
        sta = key->sta;
        sdata = key->sdata;
 
-       if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
+       if (!((key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
+                                  IEEE80211_KEY_FLAG_PUT_MIC_SPACE)) ||
              (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
                increment_tailroom_need_count(sdata);
 
@@ -1104,7 +1109,8 @@ void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
        if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
                key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 
-               if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
+               if (!((key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
+                                          IEEE80211_KEY_FLAG_PUT_MIC_SPACE)) ||
                      (key->conf.flags & IEEE80211_KEY_FLAG_RESERVE_TAILROOM)))
                        increment_tailroom_need_count(key->sdata);
        }

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 3160954fc406049e17abd1b897d07ba86ed35b02..25904af38839a202dc2c65b0b0f9864b277dc81c 100644 (file)
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -2922,7 +2922,9 @@ void ieee80211_check_fast_xmit(struct sta_info *sta)
 
                gen_iv = build.key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV;
                iv_spc = build.key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE;
-               mmic = build.key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC;
+               mmic = build.key->conf.flags &
+                       (IEEE80211_KEY_FLAG_GENERATE_MMIC |
+                        IEEE80211_KEY_FLAG_PUT_MIC_SPACE);
 
                /* don't handle software crypto */
                if (!(build.key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))

diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index b58722d9de379563b6a711e59137e4569c193186..785056cb76f6f09682b60e0ace5ceddcc17f7044 100644 (file)
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -1,7 +1,7 @@
 /*
  * Copyright 2002-2004, Instant802 Networks, Inc.
  * Copyright 2008, Jouni Malinen <j@w1.fi>
- * Copyright (C) 2016 Intel Deutschland GmbH
+ * Copyright (C) 2016-2017 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
@@ -59,8 +59,9 @@ ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
        if (info->control.hw_key &&
            (info->flags & IEEE80211_TX_CTL_DONTFRAG ||
             ieee80211_hw_check(&tx->local->hw, SUPPORTS_TX_FRAG)) &&
-           !(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC)) {
-               /* hwaccel - with no need for SW-generated MMIC */
+           !(tx->key->conf.flags & (IEEE80211_KEY_FLAG_GENERATE_MMIC |
+                                    IEEE80211_KEY_FLAG_PUT_MIC_SPACE))) {
+               /* hwaccel - with no need for SW-generated MMIC or MIC space */
                return TX_CONTINUE;
        }
 
@@ -75,8 +76,15 @@ ieee80211_tx_h_michael_mic_add(struct ieee80211_tx_data *tx)
                 skb_tailroom(skb), tail))
                return TX_DROP;
 
-       key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
        mic = skb_put(skb, MICHAEL_MIC_LEN);
+
+       if (tx->key->conf.flags & IEEE80211_KEY_FLAG_PUT_MIC_SPACE) {
+               /* Zeroed MIC can help with debug */
+               memset(mic, 0, MICHAEL_MIC_LEN);
+               return TX_CONTINUE;
+       }
+
+       key = &tx->key->conf.key[NL80211_TKIP_DATA_OFFSET_TX_MIC_KEY];
        michael_mic(key, hdr, data, data_len, mic);
        if (unlikely(info->flags & IEEE80211_TX_INTFL_TKIP_MIC_FAILURE))
                mic[0]++;