Adding valid frequency check for RXParamSetup cmd

We must check for a valid value of a frequency being sent
by the network server.

Author: Hasnain Virk

features/lorawan/lorastack/mac/LoRaMac.cpp

@@ -666,7 +666,7 @@ void LoRaMac::on_radio_tx_done(lorawan_time_t timestamp)
     _params.timers.aggregated_last_tx_time = timestamp;
 }
 
-void LoRaMac::on_radio_rx_done(const uint8_t* const payload, uint16_t size,
+void LoRaMac::on_radio_rx_done(const uint8_t *const payload, uint16_t size,
                                int16_t rssi, int8_t snr)
 {
     if (_device_class == CLASS_C && !_continuous_rx2_window_open) {

features/lorawan/lorastack/phy/LoRaPHY.cpp

@@ -1034,6 +1034,10 @@ uint8_t LoRaPHY::accept_rx_param_setup_req(rx_param_setup_req_t* params)
 {
     uint8_t status = 0x07;
 
+    if (lookup_band_for_frequency(params->frequency) < 0) {
+        status &= 0xFE;
+    }
+
     // Verify radio frequency
     if (_radio->check_rf_frequency(params->frequency) == false) {
         status &= 0xFE; // Channel frequency KO