wcn36xx: Add GTK offload info to WoWLAN resume

Having enabled GTK rekey in suspend, we need to extract the replay counter
from the firmware on resume and perform a ieee80211_gtk_rekey_notify() so
that the STA remains verified from the perspective of the AP.

In order to enable the SMD command and response we need to pack the
existing command/response structures. Given these structures are currently
unused, there's no need to backport this as a fix.

Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Tested-by: Benjamin Li <benl@squareup.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210605011140.2004643-10-bryan.odonoghue@linaro.org

drivers/net/wireless/ath/wcn36xx/hal.h

@@ -4919,7 +4919,7 @@ struct wcn36xx_hal_gtk_offload_rsp_msg {
 struct wcn36xx_hal_gtk_offload_get_info_req_msg {
 	struct wcn36xx_hal_msg_header header;
 	u8 bss_index;
-};
+} __packed;
 
 struct wcn36xx_hal_gtk_offload_get_info_rsp_msg {
 	struct wcn36xx_hal_msg_header header;
@@ -4943,7 +4943,7 @@ struct wcn36xx_hal_gtk_offload_get_info_rsp_msg {
 	u32 igtk_rekey_count;
 
 	u8 bss_index;
-};
+} __packed;
 
 struct dhcp_info {
 	/* Indicates the device mode which indicates about the DHCP activity */

drivers/net/wireless/ath/wcn36xx/main.c

@@ -1142,6 +1142,7 @@ static int wcn36xx_resume(struct ieee80211_hw *hw)
 	vif = wcn36xx_get_first_assoc_vif(wcn);
 	if (vif) {
 		wcn36xx_smd_set_power_params(wcn, false);
+		wcn36xx_smd_gtk_offload_get_info(wcn, vif);
 		wcn36xx_smd_gtk_offload(wcn, vif, false);
 		wcn36xx_smd_ipv6_ns_offload(wcn, vif, false);
 		wcn36xx_smd_arp_offload(wcn, vif, false);

drivers/net/wireless/ath/wcn36xx/smd.c

@@ -2894,6 +2894,78 @@ int wcn36xx_smd_gtk_offload(struct wcn36xx *wcn, struct ieee80211_vif *vif,
 	return ret;
 }
 
+static int wcn36xx_smd_gtk_offload_get_info_rsp(struct wcn36xx *wcn,
+						struct ieee80211_vif *vif)
+{
+	struct wcn36xx_vif *vif_priv = wcn36xx_vif_to_priv(vif);
+	struct wcn36xx_hal_gtk_offload_get_info_rsp_msg *rsp;
+	__be64 replay_ctr;
+
+	if (wcn36xx_smd_rsp_status_check(wcn->hal_buf, wcn->hal_rsp_len))
+		return -EIO;
+
+	rsp = (struct wcn36xx_hal_gtk_offload_get_info_rsp_msg *)wcn->hal_buf;
+
+	if (rsp->bss_index != vif_priv->bss_index) {
+		wcn36xx_err("gtk_offload_info invalid response bss index %d\n",
+			    rsp->bss_index);
+		return -ENOENT;
+	}
+
+	if (vif_priv->rekey_data.replay_ctr != cpu_to_le64(rsp->key_replay_counter)) {
+		replay_ctr = cpu_to_be64(rsp->key_replay_counter);
+		vif_priv->rekey_data.replay_ctr =
+			cpu_to_le64(rsp->key_replay_counter);
+		ieee80211_gtk_rekey_notify(vif, vif->bss_conf.bssid,
+					   (void *)&replay_ctr, GFP_KERNEL);
+		 wcn36xx_dbg(WCN36XX_DBG_HAL,
+			     "GTK replay counter increment %llu\n",
+			     rsp->key_replay_counter);
+	}
+
+	wcn36xx_dbg(WCN36XX_DBG_HAL,
+		    "gtk offload info status %d last_rekey_status %d "
+		    "replay_counter %llu total_rekey_count %d gtk_rekey_count %d "
+		    "igtk_rekey_count %d bss_index %d\n",
+		    rsp->status, rsp->last_rekey_status,
+		    rsp->key_replay_counter, rsp->total_rekey_count,
+		    rsp->gtk_rekey_count, rsp->igtk_rekey_count,
+		    rsp->bss_index);
+
+	return 0;
+}
+
+int wcn36xx_smd_gtk_offload_get_info(struct wcn36xx *wcn,
+				     struct ieee80211_vif *vif)
+{
+	struct wcn36xx_vif *vif_priv = wcn36xx_vif_to_priv(vif);
+	struct wcn36xx_hal_gtk_offload_get_info_req_msg msg_body;
+	int ret;
+
+	mutex_lock(&wcn->hal_mutex);
+
+	INIT_HAL_MSG(msg_body, WCN36XX_HAL_GTK_OFFLOAD_GETINFO_REQ);
+
+	msg_body.bss_index = vif_priv->bss_index;
+
+	PREPARE_HAL_BUF(wcn->hal_buf, msg_body);
+
+	ret = wcn36xx_smd_send_and_wait(wcn, msg_body.header.len);
+	if (ret) {
+		wcn36xx_err("Sending gtk_offload_get_info failed\n");
+		goto out;
+	}
+	ret = wcn36xx_smd_rsp_status_check(wcn->hal_buf, wcn->hal_rsp_len);
+	if (ret) {
+		wcn36xx_err("gtk_offload_get_info failed err=%d\n", ret);
+		goto out;
+	}
+	ret = wcn36xx_smd_gtk_offload_get_info_rsp(wcn, vif);
+out:
+	mutex_unlock(&wcn->hal_mutex);
+	return ret;
+}
+
 int wcn36xx_smd_rsp_process(struct rpmsg_device *rpdev,
 			    void *buf, int len, void *priv, u32 addr)
 {
@@ -2944,6 +3016,7 @@ int wcn36xx_smd_rsp_process(struct rpmsg_device *rpdev,
 	case WCN36XX_HAL_STOP_SCAN_OFFLOAD_RSP:
 	case WCN36XX_HAL_HOST_OFFLOAD_RSP:
 	case WCN36XX_HAL_GTK_OFFLOAD_RSP:
+	case WCN36XX_HAL_GTK_OFFLOAD_GETINFO_RSP:
 		memcpy(wcn->hal_buf, buf, len);
 		wcn->hal_rsp_len = len;
 		complete(&wcn->hal_rsp_compl);

drivers/net/wireless/ath/wcn36xx/smd.h

@@ -156,4 +156,7 @@ int wcn36xx_smd_ipv6_ns_offload(struct wcn36xx *wcn, struct ieee80211_vif *vif,
 int wcn36xx_smd_gtk_offload(struct wcn36xx *wcn, struct ieee80211_vif *vif,
 			    bool enable);
 
+int wcn36xx_smd_gtk_offload_get_info(struct wcn36xx *wcn,
+				     struct ieee80211_vif *vif);
+
 #endif	/* _SMD_H_ */