web/lib/Zend/TimeSync/Ntp.php
changeset 64 162c1de6545a
parent 19 1c2f13fd785c
child 68 ecaf28ffe26e
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/web/lib/Zend/TimeSync/Ntp.php	Fri Mar 11 15:05:35 2011 +0100
@@ -0,0 +1,431 @@
+<?php
+/**
+ * Zend Framework
+ *
+ * LICENSE
+ *
+ * This source file is subject to the new BSD license that is bundled
+ * with this package in the file LICENSE.txt.
+ * It is also available through the world-wide-web at this URL:
+ * http://framework.zend.com/license/new-bsd
+ * If you did not receive a copy of the license and are unable to
+ * obtain it through the world-wide-web, please send an email
+ * to license@zend.com so we can send you a copy immediately.
+ *
+ * @category  Zend
+ * @package   Zend_TimeSync
+ * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license   http://framework.zend.com/license/new-bsd     New BSD License
+ * @version   $Id: Ntp.php 21480 2010-03-13 22:09:26Z thomas $
+ */
+
+/**
+ * Zend_TimeSync_Protocol
+ */
+require_once 'Zend/TimeSync/Protocol.php';
+
+/**
+ * NTP Protocol handling class
+ *
+ * @category  Zend
+ * @package   Zend_TimeSync
+ * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)
+ * @license   http://framework.zend.com/license/new-bsd     New BSD License
+ */
+class Zend_TimeSync_Ntp extends Zend_TimeSync_Protocol
+{
+    /**
+     * NTP port number (123) assigned by the Internet Assigned Numbers Authority
+     *
+     * @var integer
+     */
+    protected $_port = 123;
+
+    /**
+     * NTP class constructor, sets the timeserver and port number
+     *
+     * @param string  $timeserver Adress of the timeserver to connect to
+     * @param integer $port       (Optional) Port for this timeserver
+     */
+    public function __construct($timeserver, $port = 123)
+    {
+        $this->_timeserver = 'udp://' . $timeserver;
+        if ($port !== null) {
+            $this->_port = $port;
+        }
+    }
+
+    /**
+     * Prepare local timestamp for transmission in our request packet
+     *
+     * NTP timestamps are represented as a 64-bit fixed-point number, in
+     * seconds relative to 0000 UT on 1 January 1900.  The integer part is
+     * in the first 32 bits and the fraction part in the last 32 bits
+     *
+     * @return string
+     */
+    protected function _prepare()
+    {
+        $frac   = microtime();
+        $fracba = ($frac & 0xff000000) >> 24;
+        $fracbb = ($frac & 0x00ff0000) >> 16;
+        $fracbc = ($frac & 0x0000ff00) >> 8;
+        $fracbd = ($frac & 0x000000ff);
+
+        $sec   = (time() + 2208988800);
+        $secba = ($sec & 0xff000000) >> 24;
+        $secbb = ($sec & 0x00ff0000) >> 16;
+        $secbc = ($sec & 0x0000ff00) >> 8;
+        $secbd = ($sec & 0x000000ff);
+
+        // Flags
+        $nul       = chr(0x00);
+        $nulbyte   = $nul . $nul . $nul . $nul;
+        $ntppacket = chr(0xd9) . $nul . chr(0x0a) . chr(0xfa);
+
+        /*
+         * Root delay
+         *
+         * Indicates the total roundtrip delay to the primary reference
+         * source at the root of the synchronization subnet, in seconds
+         */
+        $ntppacket .= $nul . $nul . chr(0x1c) . chr(0x9b);
+
+        /*
+         * Clock Dispersion
+         *
+         * Indicates the maximum error relative to the primary reference source at the
+         * root of the synchronization subnet, in seconds
+         */
+        $ntppacket .= $nul . chr(0x08) . chr(0xd7) . chr(0xff);
+
+        /*
+         * ReferenceClockID
+         *
+         * Identifying the particular reference clock
+         */
+        $ntppacket .= $nulbyte;
+
+        /*
+         * The local time, in timestamp format, at the peer when its latest NTP message
+         * was sent. Contanis an integer and a fractional part
+         */
+        $ntppacket .= chr($secba)  . chr($secbb)  . chr($secbc)  . chr($secbd);
+        $ntppacket .= chr($fracba) . chr($fracbb) . chr($fracbc) . chr($fracbd);
+
+        /*
+         * The local time, in timestamp format, at the peer. Contains an integer
+         * and a fractional part.
+         */
+        $ntppacket .= $nulbyte;
+        $ntppacket .= $nulbyte;
+
+        /*
+         * This is the local time, in timestamp format, when the latest NTP message from
+         * the peer arrived. Contanis an integer and a fractional part.
+         */
+        $ntppacket .= $nulbyte;
+        $ntppacket .= $nulbyte;
+
+        /*
+         * The local time, in timestamp format, at which the
+         * NTP message departed the sender. Contanis an integer
+         * and a fractional part.
+         */
+        $ntppacket .= chr($secba)  . chr($secbb)  . chr($secbc)  . chr($secbd);
+        $ntppacket .= chr($fracba) . chr($fracbb) . chr($fracbc) . chr($fracbd);
+
+        return $ntppacket;
+    }
+
+    /**
+     * Calculates a 32bit integer
+     *
+     * @param string $input
+     * @return integer
+     */
+    protected function _getInteger($input)
+    {
+        $f1  = str_pad(ord($input[0]), 2, '0', STR_PAD_LEFT);
+        $f1 .= str_pad(ord($input[1]), 2, '0', STR_PAD_LEFT);
+        $f1 .= str_pad(ord($input[2]), 2, '0', STR_PAD_LEFT);
+        $f1 .= str_pad(ord($input[3]), 2, '0', STR_PAD_LEFT);
+        return (int) $f1;
+    }
+
+    /**
+     * Calculates a 32bit signed fixed point number
+     *
+     * @param string $input
+     * @return float
+     */
+    protected function _getFloat($input)
+    {
+        $f1  = str_pad(ord($input[0]), 2, '0', STR_PAD_LEFT);
+        $f1 .= str_pad(ord($input[1]), 2, '0', STR_PAD_LEFT);
+        $f1 .= str_pad(ord($input[2]), 2, '0', STR_PAD_LEFT);
+        $f1 .= str_pad(ord($input[3]), 2, '0', STR_PAD_LEFT);
+        $f2  = $f1 >> 17;
+        $f3  = ($f1 & 0x0001FFFF);
+        $f1  = $f2 . '.' . $f3;
+        return (float) $f1;
+    }
+
+    /**
+     * Calculates a 64bit timestamp
+     *
+     * @param string $input
+     * @return float
+     */
+    protected function _getTimestamp($input)
+    {
+        $f1  = (ord($input[0]) * pow(256, 3));
+        $f1 += (ord($input[1]) * pow(256, 2));
+        $f1 += (ord($input[2]) * pow(256, 1));
+        $f1 += (ord($input[3]));
+        $f1 -= 2208988800;
+
+        $f2  = (ord($input[4]) * pow(256, 3));
+        $f2 += (ord($input[5]) * pow(256, 2));
+        $f2 += (ord($input[6]) * pow(256, 1));
+        $f2 += (ord($input[7]));
+
+        return (float) ($f1 . "." . $f2);
+    }
+
+    /**
+     * Reads the data returned from the timeserver
+     *
+     * This will return an array with binary data listing:
+     *
+     * @return array
+     * @throws Zend_TimeSync_Exception When timeserver can not be connected
+     */
+    protected function _read()
+    {
+        $flags = ord(fread($this->_socket, 1));
+        $info  = stream_get_meta_data($this->_socket);
+
+        if ($info['timed_out'] === true) {
+            fclose($this->_socket);
+            throw new Zend_TimeSync_Exception('could not connect to ' .
+                "'$this->_timeserver' on port '$this->_port', reason: 'server timed out'");
+        }
+
+        $result = array(
+            'flags'          => $flags,
+            'stratum'        => ord(fread($this->_socket, 1)),
+            'poll'           => ord(fread($this->_socket, 1)),
+            'precision'      => ord(fread($this->_socket, 1)),
+            'rootdelay'      => $this->_getFloat(fread($this->_socket, 4)),
+            'rootdispersion' => $this->_getFloat(fread($this->_socket, 4)),
+            'referenceid'    => fread($this->_socket, 4),
+            'referencestamp' => $this->_getTimestamp(fread($this->_socket, 8)),
+            'originatestamp' => $this->_getTimestamp(fread($this->_socket, 8)),
+            'receivestamp'   => $this->_getTimestamp(fread($this->_socket, 8)),
+            'transmitstamp'  => $this->_getTimestamp(fread($this->_socket, 8)),
+            'clientreceived' => microtime(true)
+        );
+
+        $this->_disconnect();
+        return $result;
+    }
+
+    /**
+     * Sends the NTP packet to the server
+     *
+     * @param  string $data Data to send to the timeserver
+     * @return void
+     */
+    protected function _write($data)
+    {
+        $this->_connect();
+
+        fwrite($this->_socket, $data);
+        stream_set_timeout($this->_socket, Zend_TimeSync::$options['timeout']);
+    }
+
+    /**
+     * Extracts the binary data returned from the timeserver
+     *
+     * @param  string|array $binary Data returned from the timeserver
+     * @return integer Difference in seconds
+     */
+    protected function _extract($binary)
+    {
+        /*
+         * Leap Indicator bit 1100 0000
+         *
+         * Code warning of impending leap-second to be inserted at the end of
+         * the last day of the current month.
+         */
+        $leap = ($binary['flags'] & 0xc0) >> 6;
+        switch($leap) {
+            case 0:
+                $this->_info['leap'] = '0 - no warning';
+                break;
+
+            case 1:
+                $this->_info['leap'] = '1 - last minute has 61 seconds';
+                break;
+
+            case 2:
+                $this->_info['leap'] = '2 - last minute has 59 seconds';
+                break;
+
+            default:
+                $this->_info['leap'] = '3 - not syncronised';
+                break;
+        }
+
+        /*
+         * Version Number bit 0011 1000
+         *
+         * This should be 3 (RFC 1305)
+         */
+        $this->_info['version'] = ($binary['flags'] & 0x38) >> 3;
+
+        /*
+         * Mode bit 0000 0111
+         *
+         * Except in broadcast mode, an NTP association is formed when two peers
+         * exchange messages and one or both of them create and maintain an
+         * instantiation of the protocol machine, called an association.
+         */
+        $mode = ($binary['flags'] & 0x07);
+        switch($mode) {
+            case 1:
+                $this->_info['mode'] = 'symetric active';
+                break;
+
+            case 2:
+                $this->_info['mode'] = 'symetric passive';
+                break;
+
+            case 3:
+                $this->_info['mode'] = 'client';
+                break;
+
+            case 4:
+                $this->_info['mode'] = 'server';
+                break;
+
+            case 5:
+                $this->_info['mode'] = 'broadcast';
+                break;
+
+            default:
+                $this->_info['mode'] = 'reserved';
+                break;
+        }
+
+        $ntpserviceid = 'Unknown Stratum ' . $binary['stratum'] . ' Service';
+
+        /*
+         * Reference Clock Identifier
+         *
+         * Identifies the particular reference clock.
+         */
+        $refid = strtoupper($binary['referenceid']);
+        switch($binary['stratum']) {
+            case 0:
+                if (substr($refid, 0, 3) === 'DCN') {
+                    $ntpserviceid = 'DCN routing protocol';
+                } else if (substr($refid, 0, 4) === 'NIST') {
+                    $ntpserviceid = 'NIST public modem';
+                } else if (substr($refid, 0, 3) === 'TSP') {
+                    $ntpserviceid = 'TSP time protocol';
+                } else if (substr($refid, 0, 3) === 'DTS') {
+                    $ntpserviceid = 'Digital Time Service';
+                }
+                break;
+
+            case 1:
+                if (substr($refid, 0, 4) === 'ATOM') {
+                    $ntpserviceid = 'Atomic Clock (calibrated)';
+                } else if (substr($refid, 0, 3) === 'VLF') {
+                    $ntpserviceid = 'VLF radio';
+                } else if ($refid === 'CALLSIGN') {
+                    $ntpserviceid = 'Generic radio';
+                } else if (substr($refid, 0, 4) === 'LORC') {
+                    $ntpserviceid = 'LORAN-C radionavigation';
+                } else if (substr($refid, 0, 4) === 'GOES') {
+                    $ntpserviceid = 'GOES UHF environment satellite';
+                } else if (substr($refid, 0, 3) === 'GPS') {
+                    $ntpserviceid = 'GPS UHF satellite positioning';
+                }
+                break;
+
+            default:
+                $ntpserviceid  = ord(substr($binary['referenceid'], 0, 1));
+                $ntpserviceid .= '.';
+                $ntpserviceid .= ord(substr($binary['referenceid'], 1, 1));
+                $ntpserviceid .= '.';
+                $ntpserviceid .= ord(substr($binary['referenceid'], 2, 1));
+                $ntpserviceid .= '.';
+                $ntpserviceid .= ord(substr($binary['referenceid'], 3, 1));
+                break;
+        }
+
+        $this->_info['ntpid'] = $ntpserviceid;
+
+        /*
+         * Stratum
+         *
+         * Indicates the stratum level of the local clock
+         */
+        switch($binary['stratum']) {
+            case 0:
+                $this->_info['stratum'] = 'undefined';
+                break;
+
+            case 1:
+                $this->_info['stratum'] = 'primary reference';
+                break;
+
+            default:
+                $this->_info['stratum'] = 'secondary reference';
+                break;
+        }
+
+        /*
+         * Indicates the total roundtrip delay to the primary reference source at the
+         * root of the synchronization subnet, in seconds.
+         *
+         * Both positive and negative values, depending on clock precision and skew, are
+         * possible.
+         */
+        $this->_info['rootdelay'] = $binary['rootdelay'];
+
+        /*
+         * Indicates the maximum error relative to the primary reference source at the
+         * root of the synchronization subnet, in seconds.
+         *
+         * Only positive values greater than zero are possible.
+         */
+        $this->_info['rootdispersion'] = $binary['rootdispersion'];
+
+        /*
+         * The roundtrip delay of the peer clock relative to the local clock
+         * over the network path between them, in seconds.
+         *
+         * Note that this variable can take on both positive and negative values,
+         * depending on clock precision and skew-error accumulation.
+         */
+        $this->_info['roundtrip']  = $binary['receivestamp'];
+        $this->_info['roundtrip'] -= $binary['originatestamp'];
+        $this->_info['roundtrip'] -= $binary['transmitstamp'];
+        $this->_info['roundtrip'] += $binary['clientreceived'];
+        $this->_info['roundtrip'] /= 2;
+
+        // The offset of the peer clock relative to the local clock, in seconds.
+        $this->_info['offset']  = $binary['receivestamp'];
+        $this->_info['offset'] -= $binary['originatestamp'];
+        $this->_info['offset'] += $binary['transmitstamp'];
+        $this->_info['offset'] -= $binary['clientreceived'];
+        $this->_info['offset'] /= 2;
+        $time = (time() - $this->_info['offset']);
+
+        return $time;
+    }
+}