mt76: fix transmission of encrypted management frames

Hardware encryption seems to break encrypted unicast mgmt tx.
Unfortunately the hardware TXWI header does not have a bit to indicate
that a frame is software encrypted, so sw-encrypted frames need to use a
different WCID. For that to work, the CCMP PN needs to be generated in
software, which makes things a bit slower, so only do it for keys that
also need to tx management frames.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h
index aa0880b..f88d9a1 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt76.h
+++ b/drivers/net/wireless/mediatek/mt76/mt76.h
@@ -129,6 +129,7 @@ struct mt76_wcid {
        bool tx_rate_set;
        u8 tx_rate_nss;
        s8 max_txpwr_adj;
+       bool sw_iv;
 };
 
 struct mt76_txq {

diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2_mac.c b/drivers/net/wireless/mediatek/mt76/mt76x2_mac.c
index f7c0df0..a7416a0 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt76x2_mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt76x2_mac.c
@@ -171,10 +171,12 @@ void mt76x2_mac_write_txwi(struct mt76x2_dev *dev, struct mt76x2_txwi *txwi,
 {
        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
        struct ieee80211_tx_rate *rate = &info->control.rates[0];
+       struct ieee80211_key_conf *key = info->control.hw_key;
        u16 rate_ht_mask = FIELD_PREP(MT_RXWI_RATE_PHY, BIT(1) | BIT(2));
        u16 txwi_flags = 0;
        u8 nss;
        s8 txpwr_adj, max_txpwr_adj;
+       u8 ccmp_pn[8];
 
        memset(txwi, 0, sizeof(*txwi));
 
@@ -185,6 +187,20 @@ void mt76x2_mac_write_txwi(struct mt76x2_dev *dev, struct mt76x2_txwi *txwi,
 
        txwi->pktid = 1;
 
+       if (wcid && wcid->sw_iv && key) {
+               u64 pn = atomic64_inc_return(&key->tx_pn);
+               ccmp_pn[0] = pn;
+               ccmp_pn[1] = pn >> 8;
+               ccmp_pn[2] = 0;
+               ccmp_pn[3] = 0x20 | (key->keyidx << 6);
+               ccmp_pn[4] = pn >> 16;
+               ccmp_pn[5] = pn >> 24;
+               ccmp_pn[6] = pn >> 32;
+               ccmp_pn[7] = pn >> 40;
+               txwi->iv = *((u32 *) &ccmp_pn[0]);
+               txwi->eiv = *((u32 *) &ccmp_pn[1]);
+       }
+
        spin_lock_bh(&dev->mt76.lock);
        if (wcid && (rate->idx < 0 || !rate->count)) {
                txwi->rate = wcid->tx_rate;

diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2_main.c b/drivers/net/wireless/mediatek/mt76/mt76x2_main.c
index fa70e6d..fb9c2db 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt76x2_main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt76x2_main.c
@@ -355,9 +355,15 @@ mt76x2_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
        if (cmd == SET_KEY) {
                key->hw_key_idx = wcid->idx;
                wcid->hw_key_idx = idx;
+               if (key->flags & IEEE80211_KEY_FLAG_RX_MGMT) {
+                       key->flags |= IEEE80211_KEY_FLAG_SW_MGMT_TX;
+                       wcid->sw_iv = true;
+               }
        } else {
-               if (idx == wcid->hw_key_idx)
+               if (idx == wcid->hw_key_idx) {
                        wcid->hw_key_idx = -1;
+                       wcid->sw_iv = true;
+               }
 
                key = NULL;
        }

diff --git a/drivers/net/wireless/mediatek/mt76/mt76x2_tx.c b/drivers/net/wireless/mediatek/mt76/mt76x2_tx.c
index 1a32e1f..534e4bf 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt76x2_tx.c
+++ b/drivers/net/wireless/mediatek/mt76/mt76x2_tx.c
@@ -36,7 +36,9 @@ void mt76x2_tx(struct ieee80211_hw *hw, struct ieee80211_tx_control *control,
 
                msta = (struct mt76x2_sta *) control->sta->drv_priv;
                wcid = &msta->wcid;
-       } else if (vif) {
+       }
+
+       if (vif || (!info->control.hw_key && wcid->hw_key_idx != -1)) {
                struct mt76x2_vif *mvif;
 
                mvif = (struct mt76x2_vif *) vif->drv_priv;
@@ -166,7 +168,7 @@ int mt76x2_tx_prepare_skb(struct mt76_dev *mdev, void *txwi,
        *tx_info = FIELD_PREP(MT_TXD_INFO_QSEL, qsel) |
                   MT_TXD_INFO_80211;
 
-       if (!wcid || wcid->hw_key_idx == 0xff)
+       if (!wcid || wcid->hw_key_idx == 0xff || wcid->sw_iv)
                *tx_info |= MT_TXD_INFO_WIV;
 
        return 0;