wifi: ath12k: support GTK rekey offload

Host sets GTK related info to firmware before WoW is enabled, and
gets rekey replay_count and then disables GTK rekey when WoW quits.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.0-03427-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.15378.4
Signed-off-by: Baochen Qiang <quic_bqiang@quicinc.com>
Acked-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://patch.msgid.link/20240604055407.12506-8-quic_bqiang@quicinc.com

drivers/net/wireless/ath/ath12k/core.h

@@ -230,6 +230,13 @@ struct ath12k_vif_cache {
 	u32 bss_conf_changed;
 };
 
+struct ath12k_rekey_data {
+	u8 kck[NL80211_KCK_LEN];
+	u8 kek[NL80211_KCK_LEN];
+	u64 replay_ctr;
+	bool enable_offload;
+};
+
 struct ath12k_vif {
 	u32 vdev_id;
 	enum wmi_vdev_type vdev_type;
@@ -286,6 +293,7 @@ struct ath12k_vif {
 	u32 punct_bitmap;
 	bool ps;
 	struct ath12k_vif_cache *cache;
+	struct ath12k_rekey_data rekey_data;
 };
 
 struct ath12k_vif_iter {

drivers/net/wireless/ath/ath12k/mac.c

@@ -2842,6 +2842,7 @@ static void ath12k_bss_assoc(struct ath12k *ar,
 	}
 
 	arvif->is_up = true;
+	arvif->rekey_data.enable_offload = false;
 
 	ath12k_dbg(ar->ab, ATH12K_DBG_MAC,
 		   "mac vdev %d up (associated) bssid %pM aid %d\n",
@@ -2889,6 +2890,8 @@ static void ath12k_bss_disassoc(struct ath12k *ar,
 
 	arvif->is_up = false;
 
+	memset(&arvif->rekey_data, 0, sizeof(arvif->rekey_data));
+
 	cancel_delayed_work(&arvif->connection_loss_work);
 }
 
@@ -8545,6 +8548,40 @@ static int ath12k_mac_op_remain_on_channel(struct ieee80211_hw *hw,
 	return ret;
 }
 
+static void ath12k_mac_op_set_rekey_data(struct ieee80211_hw *hw,
+					 struct ieee80211_vif *vif,
+					 struct cfg80211_gtk_rekey_data *data)
+{
+	struct ath12k_vif *arvif = ath12k_vif_to_arvif(vif);
+	struct ath12k_rekey_data *rekey_data = &arvif->rekey_data;
+	struct ath12k_hw *ah = ath12k_hw_to_ah(hw);
+	struct ath12k *ar = ath12k_ah_to_ar(ah, 0);
+
+	ath12k_dbg(ar->ab, ATH12K_DBG_MAC, "mac set rekey data vdev %d\n",
+		   arvif->vdev_id);
+
+	mutex_lock(&ar->conf_mutex);
+
+	memcpy(rekey_data->kck, data->kck, NL80211_KCK_LEN);
+	memcpy(rekey_data->kek, data->kek, NL80211_KEK_LEN);
+
+	/* The supplicant works on big-endian, the firmware expects it on
+	 * little endian.
+	 */
+	rekey_data->replay_ctr = get_unaligned_be64(data->replay_ctr);
+
+	arvif->rekey_data.enable_offload = true;
+
+	ath12k_dbg_dump(ar->ab, ATH12K_DBG_MAC, "kck", NULL,
+			rekey_data->kck, NL80211_KCK_LEN);
+	ath12k_dbg_dump(ar->ab, ATH12K_DBG_MAC, "kek", NULL,
+			rekey_data->kck, NL80211_KEK_LEN);
+	ath12k_dbg_dump(ar->ab, ATH12K_DBG_MAC, "replay ctr", NULL,
+			&rekey_data->replay_ctr, sizeof(rekey_data->replay_ctr));
+
+	mutex_unlock(&ar->conf_mutex);
+}
+
 static const struct ieee80211_ops ath12k_ops = {
 	.tx				= ath12k_mac_op_tx,
 	.wake_tx_queue			= ieee80211_handle_wake_tx_queue,
@@ -8560,6 +8597,7 @@ static const struct ieee80211_ops ath12k_ops = {
 	.hw_scan                        = ath12k_mac_op_hw_scan,
 	.cancel_hw_scan                 = ath12k_mac_op_cancel_hw_scan,
 	.set_key                        = ath12k_mac_op_set_key,
+	.set_rekey_data	                = ath12k_mac_op_set_rekey_data,
 	.sta_state                      = ath12k_mac_op_sta_state,
 	.sta_set_txpwr			= ath12k_mac_op_sta_set_txpwr,
 	.sta_rc_update			= ath12k_mac_op_sta_rc_update,

drivers/net/wireless/ath/ath12k/wmi.c

@@ -7091,6 +7091,56 @@ static void ath12k_wmi_event_wow_wakeup_host(struct ath12k_base *ab, struct sk_b
 	complete(&ab->wow.wakeup_completed);
 }
 
+static void ath12k_wmi_gtk_offload_status_event(struct ath12k_base *ab,
+						struct sk_buff *skb)
+{
+	const struct wmi_gtk_offload_status_event *ev;
+	struct ath12k_vif *arvif;
+	__be64 replay_ctr_be;
+	u64 replay_ctr;
+	const void **tb;
+	int ret;
+
+	tb = ath12k_wmi_tlv_parse_alloc(ab, skb, GFP_ATOMIC);
+	if (IS_ERR(tb)) {
+		ret = PTR_ERR(tb);
+		ath12k_warn(ab, "failed to parse tlv: %d\n", ret);
+		return;
+	}
+
+	ev = tb[WMI_TAG_GTK_OFFLOAD_STATUS_EVENT];
+	if (!ev) {
+		ath12k_warn(ab, "failed to fetch gtk offload status ev");
+		kfree(tb);
+		return;
+	}
+
+	rcu_read_lock();
+	arvif = ath12k_mac_get_arvif_by_vdev_id(ab, le32_to_cpu(ev->vdev_id));
+	if (!arvif) {
+		rcu_read_unlock();
+		ath12k_warn(ab, "failed to get arvif for vdev_id:%d\n",
+			    le32_to_cpu(ev->vdev_id));
+		kfree(tb);
+		return;
+	}
+
+	replay_ctr = le64_to_cpu(ev->replay_ctr);
+	arvif->rekey_data.replay_ctr = replay_ctr;
+	ath12k_dbg(ab, ATH12K_DBG_WMI, "wmi gtk offload event refresh_cnt %d replay_ctr %llu\n",
+		   le32_to_cpu(ev->refresh_cnt), replay_ctr);
+
+	/* supplicant expects big-endian replay counter */
+	replay_ctr_be = cpu_to_be64(replay_ctr);
+
+	ieee80211_gtk_rekey_notify(arvif->vif, arvif->bssid,
+				   (void *)&replay_ctr_be, GFP_ATOMIC);
+
+	rcu_read_unlock();
+
+	kfree(tb);
+}
+
 static void ath12k_wmi_op_rx(struct ath12k_base *ab, struct sk_buff *skb)
 {
 	struct wmi_cmd_hdr *cmd_hdr;
@@ -7214,6 +7264,9 @@ static void ath12k_wmi_op_rx(struct ath12k_base *ab, struct sk_buff *skb)
 	case WMI_WOW_WAKEUP_HOST_EVENTID:
 		ath12k_wmi_event_wow_wakeup_host(ab, skb);
 		break;
+	case WMI_GTK_OFFLOAD_STATUS_EVENTID:
+		ath12k_wmi_gtk_offload_status_event(ab, skb);
+		break;
 	/* TODO: Add remaining events */
 	default:
 		ath12k_dbg(ab, ATH12K_DBG_WMI, "Unknown eventid: 0x%x\n", id);
@@ -7931,3 +7984,62 @@ int ath12k_wmi_arp_ns_offload(struct ath12k *ar,
 
 	return ath12k_wmi_cmd_send(ar->wmi, skb, WMI_SET_ARP_NS_OFFLOAD_CMDID);
 }
+
+int ath12k_wmi_gtk_rekey_offload(struct ath12k *ar,
+				 struct ath12k_vif *arvif, bool enable)
+{
+	struct ath12k_rekey_data *rekey_data = &arvif->rekey_data;
+	struct wmi_gtk_rekey_offload_cmd *cmd;
+	struct sk_buff *skb;
+	__le64 replay_ctr;
+	int len;
+
+	len = sizeof(*cmd);
+	skb =  ath12k_wmi_alloc_skb(ar->wmi->wmi_ab, len);
+	if (!skb)
+		return -ENOMEM;
+
+	cmd = (struct wmi_gtk_rekey_offload_cmd *)skb->data;
+	cmd->tlv_header = ath12k_wmi_tlv_cmd_hdr(WMI_TAG_GTK_OFFLOAD_CMD, sizeof(*cmd));
+	cmd->vdev_id = cpu_to_le32(arvif->vdev_id);
+
+	if (enable) {
+		cmd->flags = cpu_to_le32(GTK_OFFLOAD_ENABLE_OPCODE);
+
+		/* the length in rekey_data and cmd is equal */
+		memcpy(cmd->kck, rekey_data->kck, sizeof(cmd->kck));
+		memcpy(cmd->kek, rekey_data->kek, sizeof(cmd->kek));
+
+		replay_ctr = cpu_to_le64(rekey_data->replay_ctr);
+		memcpy(cmd->replay_ctr, &replay_ctr,
+		       sizeof(replay_ctr));
+	} else {
+		cmd->flags = cpu_to_le32(GTK_OFFLOAD_DISABLE_OPCODE);
+	}
+
+	ath12k_dbg(ar->ab, ATH12K_DBG_WMI, "offload gtk rekey vdev: %d %d\n",
+		   arvif->vdev_id, enable);
+	return ath12k_wmi_cmd_send(ar->wmi, skb, WMI_GTK_OFFLOAD_CMDID);
+}
+
+int ath12k_wmi_gtk_rekey_getinfo(struct ath12k *ar,
+				 struct ath12k_vif *arvif)
+{
+	struct wmi_gtk_rekey_offload_cmd *cmd;
+	struct sk_buff *skb;
+	int len;
+
+	len = sizeof(*cmd);
+	skb =  ath12k_wmi_alloc_skb(ar->wmi->wmi_ab, len);
+	if (!skb)
+		return -ENOMEM;
+
+	cmd = (struct wmi_gtk_rekey_offload_cmd *)skb->data;
+	cmd->tlv_header = ath12k_wmi_tlv_cmd_hdr(WMI_TAG_GTK_OFFLOAD_CMD, sizeof(*cmd));
+	cmd->vdev_id = cpu_to_le32(arvif->vdev_id);
+	cmd->flags = cpu_to_le32(GTK_OFFLOAD_REQUEST_STATUS_OPCODE);
+
+	ath12k_dbg(ar->ab, ATH12K_DBG_WMI, "get gtk rekey vdev_id: %d\n",
+		   arvif->vdev_id);
+	return ath12k_wmi_cmd_send(ar->wmi, skb, WMI_GTK_OFFLOAD_CMDID);
+}

drivers/net/wireless/ath/ath12k/wmi.h

@@ -5374,6 +5374,41 @@ struct wmi_set_arp_ns_offload_cmd {
 	 */
 } __packed;
 
+#define GTK_OFFLOAD_OPCODE_MASK             0xFF000000
+#define GTK_OFFLOAD_ENABLE_OPCODE           0x01000000
+#define GTK_OFFLOAD_DISABLE_OPCODE          0x02000000
+#define GTK_OFFLOAD_REQUEST_STATUS_OPCODE   0x04000000
+
+#define GTK_OFFLOAD_KEK_BYTES       16
+#define GTK_OFFLOAD_KCK_BYTES       16
+#define GTK_REPLAY_COUNTER_BYTES    8
+#define WMI_MAX_KEY_LEN             32
+#define IGTK_PN_SIZE                6
+
+struct wmi_gtk_offload_status_event {
+	__le32 vdev_id;
+	__le32 flags;
+	__le32 refresh_cnt;
+	__le64 replay_ctr;
+	u8 igtk_key_index;
+	u8 igtk_key_length;
+	u8 igtk_key_rsc[IGTK_PN_SIZE];
+	u8 igtk_key[WMI_MAX_KEY_LEN];
+	u8 gtk_key_index;
+	u8 gtk_key_length;
+	u8 gtk_key_rsc[GTK_REPLAY_COUNTER_BYTES];
+	u8 gtk_key[WMI_MAX_KEY_LEN];
+} __packed;
+
+struct wmi_gtk_rekey_offload_cmd {
+	__le32 tlv_header;
+	__le32 vdev_id;
+	__le32 flags;
+	u8 kek[GTK_OFFLOAD_KEK_BYTES];
+	u8 kck[GTK_OFFLOAD_KCK_BYTES];
+	u8 replay_ctr[GTK_REPLAY_COUNTER_BYTES];
+} __packed;
+
 void ath12k_wmi_init_qcn9274(struct ath12k_base *ab,
 			     struct ath12k_wmi_resource_config_arg *config);
 void ath12k_wmi_init_wcn7850(struct ath12k_base *ab,
@@ -5543,5 +5578,9 @@ int ath12k_wmi_arp_ns_offload(struct ath12k *ar,
 			      struct ath12k_vif *arvif,
 			      struct wmi_arp_ns_offload_arg *offload,
 			      bool enable);
+int ath12k_wmi_gtk_rekey_offload(struct ath12k *ar,
+				 struct ath12k_vif *arvif, bool enable);
+int ath12k_wmi_gtk_rekey_getinfo(struct ath12k *ar,
+				 struct ath12k_vif *arvif);
 
 #endif

drivers/net/wireless/ath/ath12k/wow.c

@@ -21,7 +21,9 @@
 
 static const struct wiphy_wowlan_support ath12k_wowlan_support = {
 	.flags = WIPHY_WOWLAN_DISCONNECT |
-		 WIPHY_WOWLAN_MAGIC_PKT,
+		 WIPHY_WOWLAN_MAGIC_PKT |
+		 WIPHY_WOWLAN_SUPPORTS_GTK_REKEY |
+		 WIPHY_WOWLAN_GTK_REKEY_FAILURE,
 	.pattern_min_len = WOW_MIN_PATTERN_SIZE,
 	.pattern_max_len = WOW_MAX_PATTERN_SIZE,
 	.max_pkt_offset = WOW_MAX_PKT_OFFSET,
@@ -762,6 +764,41 @@ static int ath12k_wow_arp_ns_offload(struct ath12k *ar, bool enable)
 	return 0;
 }
 
+static int ath12k_gtk_rekey_offload(struct ath12k *ar, bool enable)
+{
+	struct ath12k_vif *arvif;
+	int ret;
+
+	lockdep_assert_held(&ar->conf_mutex);
+
+	list_for_each_entry(arvif, &ar->arvifs, list) {
+		if (arvif->vdev_type != WMI_VDEV_TYPE_STA ||
+		    !arvif->is_up ||
+		    !arvif->rekey_data.enable_offload)
+			continue;
+
+		/* get rekey info before disable rekey offload */
+		if (!enable) {
+			ret = ath12k_wmi_gtk_rekey_getinfo(ar, arvif);
+			if (ret) {
+				ath12k_warn(ar->ab, "failed to request rekey info vdev %i, ret %d\n",
+					    arvif->vdev_id, ret);
+				return ret;
+			}
+		}
+
+		ret = ath12k_wmi_gtk_rekey_offload(ar, arvif, enable);
+
+		if (ret) {
+			ath12k_warn(ar->ab, "failed to offload gtk reky vdev %i: enable %d, ret %d\n",
+				    arvif->vdev_id, enable, ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
 static int ath12k_wow_protocol_offload(struct ath12k *ar, bool enable)
 {
 	int ret;
@@ -773,6 +810,13 @@ static int ath12k_wow_protocol_offload(struct ath12k *ar, bool enable)
 		return ret;
 	}
 
+	ret = ath12k_gtk_rekey_offload(ar, enable);
+	if (ret) {
+		ath12k_warn(ar->ab, "failed to offload gtk rekey %d %d\n",
+			    enable, ret);
+		return ret;
+	}
+
 	return 0;
 }