[PATCH 06/23] wifi: mt76: mt7925: implement NAN key management MCU command

[Sean Wang <sean.wang@kernel.org>]

From: Chengwei Yu <chengwei.yu@mediatek.com>

Add mt7925_nan_manage_key_cmd() and mt7925_nan_key_mgmt_tlv() to
install and remove NAN group and pairwise keys via
NAN_UNI_CMD_KEY_MANAGEMENT. The TLV builder covers all firmware key
types: NM-TK, ND-TK (unicast), TX/RX GTK (multicast data) and
TX/RX IGTK/BIGTK (multicast management).

Follows the same skb + mt76_connac_mcu_add_tlv() pattern as other NAN
commands (mt7925_nan_enable(), mt7925_nan_change_configure()) rather
than hand-assembling a packed struct, so it composes naturally with
the existing NAN command helpers.

Key material is grouped into struct mt7925_nan_key_info so callers
pass one pointer instead of five arguments; init/key_exist firmware
flags are hardcoded 1/0 since every real caller uses the same values.

Co-developed-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Chengwei Yu <chengwei.yu@mediatek.com>
---
 .../net/wireless/mediatek/mt76/mt7925/nan.c   | 122 ++++++++++++++++++
 .../net/wireless/mediatek/mt76/mt7925/nan.h   |  72 +++++++++++
 2 files changed, 194 insertions(+)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/nan.c b/drivers/net/wireless/mediatek/mt76/mt7925/nan.c
index 73e45be8b40e..0579501207eb 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7925/nan.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7925/nan.c
@@ -897,6 +897,128 @@ void mt7925_nan_stop_mac_randomization(struct ieee80211_vif *vif)
 	cancel_delayed_work_sync(&mvif->nan.mac_rand_work);
 }
 
+static int
+mt7925_nan_key_mgmt_tlv(struct sk_buff *skb,
+			enum mt7925_nan_key_operation key_op,
+			enum mt7925_nan_key_type key_type,
+			u16 wtbl_entry,
+			const u8 *local_addr,
+			const u8 *peer_addr,
+			const struct mt7925_nan_key_info *key)
+{
+	struct mt7925_nan_key_mgmt_tlv *key_mgmt_tlv = NULL;
+	struct tlv *tlv = NULL;
+
+	if (!skb)
+		return -EINVAL;
+
+	tlv = mt76_connac_mcu_add_tlv(skb, NAN_UNI_CMD_KEY_MANAGEMENT,
+				      sizeof(struct mt7925_nan_key_mgmt_tlv));
+	if (!tlv)
+		return -ENOMEM;
+
+	key_mgmt_tlv = (struct mt7925_nan_key_mgmt_tlv *)tlv;
+	key_mgmt_tlv->op = (u8)key_op;
+	key_mgmt_tlv->key_type = (u8)key_type;
+	key_mgmt_tlv->wtbl_idx = cpu_to_le16(wtbl_entry);
+	key_mgmt_tlv->init = 1;
+	key_mgmt_tlv->key_exist = 0;
+	key_mgmt_tlv->is_nmi_tk = 0;
+
+	memcpy(key_mgmt_tlv->local_addr, local_addr, ETH_ALEN);
+	memcpy(key_mgmt_tlv->peer_addr, peer_addr, ETH_ALEN);
+
+	switch (key_type) {
+	case NAN_KEY_TYPE_NMI_CXT_MGMT_KEY:
+		key_mgmt_tlv->nmi_key_idx = 0;
+		key_mgmt_tlv->is_nmi_tk = true;
+		break;
+	case NAN_KEY_TYPE_MC_TX_KEY:
+	case NAN_KEY_TYPE_MC_MGMT_TX_KEY:
+		/* TX GTK/IGTK/BIGTK: NDI-indexed slot; NDC ID not yet tracked */
+		key_mgmt_tlv->ndi_idx = 0;
+		break;
+	case NAN_KEY_TYPE_MC_RX_KEY:
+	case NAN_KEY_TYPE_MC_MGMT_RX_KEY:
+		key_mgmt_tlv->mc_rx_idx = (u8)wtbl_entry;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (key_op == NAN_KEY_OP_SET_KEY) {
+		key_mgmt_tlv->algorithm_id = key->algo_id;
+		key_mgmt_tlv->key_id = key->key_id;
+		key_mgmt_tlv->key_len = key->key_len;
+
+		if (key_type == NAN_KEY_TYPE_MC_MGMT_RX_KEY && key->pn) {
+			memcpy(key_mgmt_tlv->key_rsc, key->pn,
+			       min_t(size_t, NAN_PACKET_NUMBER_LEN,
+				     sizeof(key_mgmt_tlv->key_rsc)));
+		}
+
+		if (key->key_data) {
+			memcpy(key_mgmt_tlv->key_material, key->key_data,
+			       min_t(size_t, key->key_len,
+				     sizeof(key_mgmt_tlv->key_material)));
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * mt7925_nan_manage_key_cmd - Install/remove a NAN group or pairwise key
+ * @dev: mt792x device pointer
+ * @key_op: NAN_KEY_OP_SET_KEY or NAN_KEY_OP_CLS_KEY
+ * @key_type: which NAN key slot this targets (enum mt7925_nan_key_type)
+ * @wtbl_entry: WTBL index the key is bound to (WTBL_RESERVED_ENTRY invalid)
+ * @local_addr: local MAC address for this key context
+ * @peer_addr: peer MAC address for this key context
+ * @key: key material; key->key_data required for NAN_KEY_OP_SET_KEY
+ *
+ * There are no other callers yet; NAN group key installation added by a
+ * later change calls into this single command path.
+ */
+int
+mt7925_nan_manage_key_cmd(struct mt792x_dev *dev,
+			  enum mt7925_nan_key_operation key_op,
+			  enum mt7925_nan_key_type key_type,
+			  u16 wtbl_entry,
+			  const u8 *local_addr,
+			  const u8 *peer_addr,
+			  const struct mt7925_nan_key_info *key)
+{
+	struct mt76_dev *mdev = &dev->mt76;
+	struct mt7925_nan_common_hdr *hdr = NULL;
+	struct sk_buff *skb = NULL;
+	int ret;
+
+	if (!key || !local_addr || !peer_addr ||
+	    key_type >= NAN_KEY_TYPE_NUM ||
+	    wtbl_entry == WTBL_RESERVED_ENTRY ||
+	    (key_op == NAN_KEY_OP_SET_KEY && !key->key_data))
+		return -EINVAL;
+
+	skb = mt76_mcu_msg_alloc(mdev, NULL,
+				 sizeof(struct mt7925_nan_common_hdr) +
+				 sizeof(struct mt7925_nan_key_mgmt_tlv));
+	if (!skb)
+		return -ENOMEM;
+
+	hdr = (struct mt7925_nan_common_hdr *)skb_put(skb, sizeof(*hdr));
+	memset(hdr, 0, sizeof(*hdr));
+
+	ret = mt7925_nan_key_mgmt_tlv(skb, key_op, key_type, wtbl_entry,
+				      local_addr, peer_addr, key);
+	if (ret) {
+		dev_kfree_skb(skb);
+		return ret;
+	}
+
+	return mt76_mcu_skb_send_msg(mdev, skb, MCU_UNI_CMD(NAN), true);
+}
+
 static int mt7925_nan_avail_ctrl_tlv(struct sk_buff *skb,
 				     struct ieee80211_vif *vif)
 {
diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/nan.h b/drivers/net/wireless/mediatek/mt76/mt7925/nan.h
index 3a14ec384e4f..f15a16b773bb 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7925/nan.h
+++ b/drivers/net/wireless/mediatek/mt76/mt7925/nan.h
@@ -109,6 +109,24 @@ enum nan_disc_event_type {
 	NAN_EVENT_ID_JOINED_CLUSTER		= 2,
 };
 
+enum mt7925_nan_key_operation {
+	NAN_KEY_OP_SET_KEY,
+	NAN_KEY_OP_CLS_KEY,
+};
+
+enum mt7925_nan_key_type {
+	NAN_KEY_TYPE_NMI_CXT_MGMT_KEY,	/* NM-TK: NAN Management pairwise key */
+	NAN_KEY_TYPE_ND_TK,		/* ND-TK: NAN Data pairwise key */
+	NAN_KEY_TYPE_MC_TX_KEY,		/* TX GTK (multicast data) */
+	NAN_KEY_TYPE_MC_RX_KEY,		/* RX GTK (multicast data) */
+	NAN_KEY_TYPE_MC_MGMT_TX_KEY,	/* TX IGTK/BIGTK (multicast mgmt) */
+	NAN_KEY_TYPE_MC_MGMT_RX_KEY,	/* RX IGTK/BIGTK (multicast mgmt) */
+	NAN_KEY_TYPE_NUM,
+};
+
+#define WTBL_RESERVED_ENTRY	0xFFFF
+#define NAN_PACKET_NUMBER_LEN	6
+
 /* bit indices into mt792x_dev->nan_deferred_pending, set from the atomic
  * MCU-event RX path and consumed by mt7925_nan_deferred_work()
  */
@@ -478,6 +496,35 @@ struct mt7925_nan_update_phy_setting_tlv {
 	struct mt7925_nan_phy_setting phy_5g;
 } __packed __aligned(4);
 
+struct mt7925_nan_key_mgmt_tlv {
+	__le16 tag;
+	__le16 len;
+
+	u8 op;			/* enum mt7925_nan_key_operation */
+	u8 key_type;		/* enum mt7925_nan_key_type */
+	__le16 wtbl_idx;
+	u8 init;
+	u8 key_exist;
+	u8 is_nmi_tk;
+	u8 reserved0;
+
+	u8 local_addr[ETH_ALEN];
+	u8 peer_addr[ETH_ALEN];
+
+	union {
+		u8 nmi_key_idx;
+		u8 ndi_idx;
+		u8 mc_rx_idx;
+	};
+	u8 algorithm_id;
+	u8 key_id;
+	u8 key_len;
+
+	u8 key_rsc[NAN_PACKET_NUMBER_LEN];
+	u8 reserved1[2];
+	u8 key_material[32];
+} __packed __aligned(4);
+
 /* NAN Low Power Control Command */
 struct mt7925_nan_lowpower_ctrl_tlv {
 	__le16 tag;
@@ -528,6 +575,31 @@ void mt7925_nan_stop_mac_randomization(struct ieee80211_vif *vif);
 
 int mt7925_nan_send_lowpower_ctrl_cmd(struct mt792x_dev *dev, bool enable);
 
+/**
+ * struct mt7925_nan_key_info - key material for mt7925_nan_manage_key_cmd
+ * @algo_id:  firmware cipher algorithm ID (from mt7925_mcu_get_cipher())
+ * @key_id:   key index (1-2 for GTK, 4-7 for IGTK/BIGTK)
+ * @key_len:  key material length in bytes (16 or 32)
+ * @key_data: key bytes; must be non-NULL for SET_KEY operations
+ * @pn:       6-byte packet number / RSC; only used for MC_MGMT_RX_KEY,
+ *            pass NULL for all other key types
+ */
+struct mt7925_nan_key_info {
+	u8 algo_id;
+	u8 key_id;
+	u8 key_len;
+	const u8 *key_data;
+	const u8 *pn;
+};
+
+int mt7925_nan_manage_key_cmd(struct mt792x_dev *dev,
+			      enum mt7925_nan_key_operation key_op,
+			      enum mt7925_nan_key_type key_type,
+			      u16 wtbl_entry,
+			      const u8 *local_addr,
+			      const u8 *peer_addr,
+			      const struct mt7925_nan_key_info *key);
+
 void mt7925_nan_local_sched_changed(struct mt792x_dev *dev,
 				    struct ieee80211_vif *vif);
 
-- 
2.43.0