wifi: rtl8xxxu: add hw crypto support for AP mode

Add a custom function for allocating entries in the sec cam. This allows
us to store multiple keys with the same keyidx.

The maximum number of sec cam entries for 8188f is 16 according to the
vendor driver. Add the number to rtl8xxxu_fileops, so that other chips
which might support more entries, can set a different number there.

Set the bssid as mac address for group keys instead of just using the
ethernet broadcast address and use BIT(6) in the sec cam ctrl entry
for differentiating them from pairwise keys like in the vendor driver.

Add the TXDESC_EN_DESC_ID bit and the hw_key_idx to tx
broadcast/multicast packets in AP mode.

Finally, allow the usage of rtl8xxxu_set_key() for AP mode.

Signed-off-by: Martin Kaistra <martin.kaistra@linutronix.de>
Reviewed-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20231222101442.626837-20-martin.kaistra@linutronix.de

1 files changed, 38 insertions, 10 deletions

diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
index 07cfce55a519..fb2bb042683a 100644
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
@@ -4559,8 +4559,10 @@ static void rtl8xxxu_cam_write(struct rtl8xxxu_priv *priv,
 	 * This is a bit of a hack - the lower bits of the cipher
 	 * suite selector happens to match the cipher index in the CAM
 	 */
-	addr = key->keyidx << CAM_CMD_KEY_SHIFT;
+	addr = key->hw_key_idx << CAM_CMD_KEY_SHIFT;
 	ctrl = (key->cipher & 0x0f) << 2 | key->keyidx | CAM_WRITE_VALID;
+	if (!(key->flags & IEEE80211_KEY_FLAG_PAIRWISE))
+		ctrl |= BIT(6);
 
 	for (j = 5; j >= 0; j--) {
 		switch (j) {
@@ -5546,13 +5548,14 @@ static void rtl8xxxu_tx(struct ieee80211_hw *hw,
 	struct rtl8xxxu_tx_urb *tx_urb;
 	struct ieee80211_sta *sta = NULL;
 	struct ieee80211_vif *vif = tx_info->control.vif;
+	struct rtl8xxxu_vif *rtlvif = (struct rtl8xxxu_vif *)vif->drv_priv;
 	struct device *dev = &priv->udev->dev;
 	u32 queue, rts_rate;
 	u16 pktlen = skb->len;
 	int tx_desc_size = priv->fops->tx_desc_size;
 	u8 macid;
 	int ret;
-	bool ampdu_enable, sgi = false, short_preamble = false;
+	bool ampdu_enable, sgi = false, short_preamble = false, bmc = false;
 
 	if (skb_headroom(skb) < tx_desc_size) {
 		dev_warn(dev,
@@ -5594,10 +5597,14 @@ static void rtl8xxxu_tx(struct ieee80211_hw *hw,
 		tx_desc->txdw0 =
 			TXDESC_OWN | TXDESC_FIRST_SEGMENT | TXDESC_LAST_SEGMENT;
 	if (is_multicast_ether_addr(ieee80211_get_DA(hdr)) ||
-	    is_broadcast_ether_addr(ieee80211_get_DA(hdr)))
+	    is_broadcast_ether_addr(ieee80211_get_DA(hdr))) {
 		tx_desc->txdw0 |= TXDESC_BROADMULTICAST;
+		bmc = true;
+	}
+
 
 	tx_desc->txdw1 = cpu_to_le32(queue << TXDESC_QUEUE_SHIFT);
+	macid = rtl8xxxu_get_macid(priv, sta);
 
 	if (tx_info->control.hw_key) {
 		switch (tx_info->control.hw_key->cipher) {
@@ -5612,6 +5619,10 @@ static void rtl8xxxu_tx(struct ieee80211_hw *hw,
 		default:
 			break;
 		}
+		if (bmc && rtlvif->hw_key_idx != 0xff) {
+			tx_desc->txdw1 |= TXDESC_EN_DESC_ID;
+			macid = rtlvif->hw_key_idx;
+		}
 	}
 
 	/* (tx_info->flags & IEEE80211_TX_CTL_AMPDU) && */
@@ -5655,7 +5666,6 @@ static void rtl8xxxu_tx(struct ieee80211_hw *hw,
 	else
 		rts_rate = 0;
 
-	macid = rtl8xxxu_get_macid(priv, sta);
 	priv->fops->fill_txdesc(hw, hdr, tx_info, tx_desc, sgi, short_preamble,
 				ampdu_enable, rts_rate, macid);
 
@@ -6667,6 +6677,7 @@ static int rtl8xxxu_add_interface(struct ieee80211_hw *hw,
 
 	priv->vifs[port_num] = vif;
 	rtlvif->port_num = port_num;
+	rtlvif->hw_key_idx = 0xff;
 
 	rtl8xxxu_set_linktype(priv, vif->type, port_num);
 	ether_addr_copy(priv->mac_addr, vif->addr);
@@ -6843,11 +6854,19 @@ static int rtl8xxxu_set_rts_threshold(struct ieee80211_hw *hw, u32 rts)
 	return 0;
 }
 
+static int rtl8xxxu_get_free_sec_cam(struct ieee80211_hw *hw)
+{
+	struct rtl8xxxu_priv *priv = hw->priv;
+
+	return find_first_zero_bit(priv->cam_map, priv->fops->max_sec_cam_num);
+}
+
 static int rtl8xxxu_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
 			    struct ieee80211_vif *vif,
 			    struct ieee80211_sta *sta,
 			    struct ieee80211_key_conf *key)
 {
+	struct rtl8xxxu_vif *rtlvif = (struct rtl8xxxu_vif *)vif->drv_priv;
 	struct rtl8xxxu_priv *priv = hw->priv;
 	struct device *dev = &priv->udev->dev;
 	u8 mac_addr[ETH_ALEN];
@@ -6859,9 +6878,6 @@ static int rtl8xxxu_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
 	dev_dbg(dev, "%s: cmd %02x, cipher %08x, index %i\n",
 		__func__, cmd, key->cipher, key->keyidx);
 
-	if (vif->type != NL80211_IFTYPE_STATION)
-		return -EOPNOTSUPP;
-
 	if (key->keyidx > 3)
 		return -EOPNOTSUPP;
 
@@ -6885,7 +6901,7 @@ static int rtl8xxxu_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
 		ether_addr_copy(mac_addr, sta->addr);
 	} else {
 		dev_dbg(dev, "%s: group key\n", __func__);
-		eth_broadcast_addr(mac_addr);
+		ether_addr_copy(mac_addr, vif->bss_conf.bssid);
 	}
 
 	val16 = rtl8xxxu_read16(priv, REG_CR);
@@ -6899,16 +6915,28 @@ static int rtl8xxxu_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
 
 	switch (cmd) {
 	case SET_KEY:
-		key->hw_key_idx = key->keyidx;
+
+		retval = rtl8xxxu_get_free_sec_cam(hw);
+		if (retval < 0)
+			return -EOPNOTSUPP;
+
+		key->hw_key_idx = retval;
+
+		if (vif->type == NL80211_IFTYPE_AP && !(key->flags & IEEE80211_KEY_FLAG_PAIRWISE))
+			rtlvif->hw_key_idx = key->hw_key_idx;
+
 		key->flags |= IEEE80211_KEY_FLAG_GENERATE_IV;
 		rtl8xxxu_cam_write(priv, key, mac_addr);
+		set_bit(key->hw_key_idx, priv->cam_map);
 		retval = 0;
 		break;
 	case DISABLE_KEY:
 		rtl8xxxu_write32(priv, REG_CAM_WRITE, 0x00000000);
 		val32 = CAM_CMD_POLLING | CAM_CMD_WRITE |
-			key->keyidx << CAM_CMD_KEY_SHIFT;
+			key->hw_key_idx << CAM_CMD_KEY_SHIFT;
 		rtl8xxxu_write32(priv, REG_CAM_CMD, val32);
+		rtlvif->hw_key_idx = 0xff;
+		clear_bit(key->hw_key_idx, priv->cam_map);
 		retval = 0;
 		break;
 	default: