fetch.php

<?php
    $signedVersionsURL = "https://api.ipsw.me/v2.1/firmwares.json/condensed"; 
    $ch = curl_init();
		curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
		curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
		curl_setopt($ch, CURLOPT_URL,$signedVersionsURL);
		$result = curl_exec($ch);
		curl_close($ch);
		$data = json_decode($result, true);
		
		$firmwares = $data['devices'][$deviceInfo['deviceIdentifier']]['firmwares'];
		$countFirmwares = count($firmwares);
		for($i = 0; $i < $countFirmwares; $i++) {
			$current = $firmwares[$i];
			if($current['signed'] == true)
				$firmware[] = $current;
		}