hostapd: add ubus method for requesting link measurements

Add a ubus method to request link-measurements from connected STAs.

In addition to the STAs address, the used and maximum transmit power can
be provided by the external process for the link-measurement. If they
are not provided, 0 is used as the default value.

Signed-off-by: David Bauer <mail@david-bauer.net>
(cherry picked from commit 965aa33a18)

package/network/services/hostapd/src/src/ap/ubus.c

@@ -1248,6 +1248,70 @@ hostapd_rrm_beacon_req(struct ubus_context *ctx, struct ubus_object *obj,
 	return 0;
 }
 
+enum {
+	LM_REQ_ADDR,
+	LM_REQ_TX_POWER_USED,
+	LM_REQ_TX_POWER_MAX,
+	__LM_REQ_MAX,
+};
+
+static const struct blobmsg_policy lm_req_policy[__LM_REQ_MAX] = {
+	[LM_REQ_ADDR] = { "addr", BLOBMSG_TYPE_STRING },
+	[LM_REQ_TX_POWER_USED] = { "tx-power-used", BLOBMSG_TYPE_INT32 },
+	[LM_REQ_TX_POWER_MAX] = { "tx-power-max", BLOBMSG_TYPE_INT32 },
+};
+
+static int
+hostapd_rrm_lm_req(struct ubus_context *ctx, struct ubus_object *obj,
+		   struct ubus_request_data *ureq, const char *method,
+		   struct blob_attr *msg)
+{
+	struct hostapd_data *hapd = container_of(obj, struct hostapd_data, ubus.obj);
+	struct blob_attr *tb[__LM_REQ_MAX];
+	struct wpabuf *buf;
+	u8 addr[ETH_ALEN];
+	int ret;
+	int8_t txp_used, txp_max;
+
+	txp_used = 0;
+	txp_max = 0;
+
+	blobmsg_parse(lm_req_policy, __LM_REQ_MAX, tb, blob_data(msg), blob_len(msg));
+
+	if (!tb[LM_REQ_ADDR])
+		return UBUS_STATUS_INVALID_ARGUMENT;
+
+	if (tb[LM_REQ_TX_POWER_USED])
+		txp_used = (int8_t) blobmsg_get_u32(tb[LM_REQ_TX_POWER_USED]);
+
+	if (tb[LM_REQ_TX_POWER_MAX])
+		txp_max = (int8_t) blobmsg_get_u32(tb[LM_REQ_TX_POWER_MAX]);
+
+	if (hwaddr_aton(blobmsg_data(tb[LM_REQ_ADDR]), addr))
+		return UBUS_STATUS_INVALID_ARGUMENT;
+
+	buf = wpabuf_alloc(5);
+	if (!buf)
+		return UBUS_STATUS_UNKNOWN_ERROR;
+
+	wpabuf_put_u8(buf, WLAN_ACTION_RADIO_MEASUREMENT);
+	wpabuf_put_u8(buf, WLAN_RRM_LINK_MEASUREMENT_REQUEST);
+	wpabuf_put_u8(buf, 1);
+	/* TX-Power used */
+	wpabuf_put_u8(buf, txp_used);
+	/* Max TX Power */
+	wpabuf_put_u8(buf, txp_max);
+
+	ret = hostapd_drv_send_action(hapd, hapd->iface->freq, 0, addr,
+				      wpabuf_head(buf), wpabuf_len(buf));
+
+	wpabuf_free(buf);
+	if (ret < 0)
+		return -ret;
+
+	return 0;
+}
+
 
 #ifdef CONFIG_WNM_AP
 
@@ -1441,6 +1505,7 @@ static const struct ubus_method bss_methods[] = {
 	UBUS_METHOD_NOARG("rrm_nr_list", hostapd_rrm_nr_list),
 	UBUS_METHOD("rrm_nr_set", hostapd_rrm_nr_set, nr_set_policy),
 	UBUS_METHOD("rrm_beacon_req", hostapd_rrm_beacon_req, beacon_req_policy),
+	UBUS_METHOD("link_measurement_req", hostapd_rrm_lm_req, lm_req_policy),
 #ifdef CONFIG_WNM_AP
 	UBUS_METHOD("wnm_disassoc_imminent", hostapd_wnm_disassoc_imminent, wnm_disassoc_policy),
 	UBUS_METHOD("bss_transition_request", hostapd_bss_transition_request, bss_tr_policy),