| <?php |
| |
| namespace RobThree\Auth\Providers\Time; |
| |
| /** |
| * Takes the time from any NTP server |
| */ |
| class NTPTimeProvider implements ITimeProvider |
| { |
| /** @var string */ |
| public $host; |
| |
| /** @var int */ |
| public $port; |
| |
| /** @var int */ |
| public $timeout; |
| |
| /** |
| * @param string $host |
| * @param int $port |
| * @param int $timeout |
| */ |
| public function __construct($host = 'time.google.com', $port = 123, $timeout = 1) |
| { |
| $this->host = $host; |
| |
| if (!is_int($port) || $port <= 0 || $port > 65535) { |
| throw new TimeException('Port must be 0 < port < 65535'); |
| } |
| $this->port = $port; |
| |
| if (!is_int($timeout) || $timeout < 0) { |
| throw new TimeException('Timeout must be >= 0'); |
| } |
| $this->timeout = $timeout; |
| } |
| |
| /** |
| * {@inheritdoc} |
| */ |
| public function getTime() |
| { |
| try { |
| /* Create a socket and connect to NTP server */ |
| $sock = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP); |
| socket_set_option($sock, SOL_SOCKET, SO_RCVTIMEO, ['sec' => $this->timeout, 'usec' => 0]); |
| socket_connect($sock, $this->host, $this->port); |
| |
| /* Send request */ |
| $msg = "\010" . str_repeat("\0", 47); |
| socket_send($sock, $msg, strlen($msg), 0); |
| |
| /* Receive response and close socket */ |
| if (socket_recv($sock, $recv, 48, MSG_WAITALL) === false) { |
| throw new \Exception(socket_strerror(socket_last_error($sock))); |
| } |
| socket_close($sock); |
| |
| /* Interpret response */ |
| $data = unpack('N12', $recv); |
| $timestamp = (int) sprintf('%u', $data[9]); |
| |
| /* NTP is number of seconds since 0000 UT on 1 January 1900 Unix time is seconds since 0000 UT on 1 January 1970 */ |
| return $timestamp - 2208988800; |
| } catch (\Exception $ex) { |
| throw new TimeException(sprintf('Unable to retrieve time from %s (%s)', $this->host, $ex->getMessage())); |
| } |
| } |
| } |