372 lines
8.4 KiB
PHP
372 lines
8.4 KiB
PHP
<?php
|
|
/**
|
|
* SimplePie
|
|
*
|
|
* A PHP-Based RSS and Atom Feed Framework.
|
|
* Takes the hard work out of managing a complete RSS/Atom solution.
|
|
*
|
|
* Copyright (c) 2004-2012, Ryan Parman, Geoffrey Sneddon, Ryan McCue, and contributors
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without modification, are
|
|
* permitted provided that the following conditions are met:
|
|
*
|
|
* * Redistributions of source code must retain the above copyright notice, this list of
|
|
* conditions and the following disclaimer.
|
|
*
|
|
* * Redistributions in binary form must reproduce the above copyright notice, this list
|
|
* of conditions and the following disclaimer in the documentation and/or other materials
|
|
* provided with the distribution.
|
|
*
|
|
* * Neither the name of the SimplePie Team nor the names of its contributors may be used
|
|
* to endorse or promote products derived from this software without specific prior
|
|
* written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS
|
|
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
|
|
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS
|
|
* AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
|
|
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
* @package SimplePie
|
|
* @version 1.3.1
|
|
* @copyright 2004-2012 Ryan Parman, Geoffrey Sneddon, Ryan McCue
|
|
* @author Ryan Parman
|
|
* @author Geoffrey Sneddon
|
|
* @author Ryan McCue
|
|
* @link http://simplepie.org/ SimplePie
|
|
* @license http://www.opensource.org/licenses/bsd-license.php BSD License
|
|
*/
|
|
|
|
|
|
/**
|
|
* Decode 'gzip' encoded HTTP data
|
|
*
|
|
* @package SimplePie
|
|
* @subpackage HTTP
|
|
* @link http://www.gzip.org/format.txt
|
|
*/
|
|
class SimplePie_gzdecode
|
|
{
|
|
/**
|
|
* Compressed data
|
|
*
|
|
* @access private
|
|
* @var string
|
|
* @see gzdecode::$data
|
|
*/
|
|
var $compressed_data;
|
|
|
|
/**
|
|
* Size of compressed data
|
|
*
|
|
* @access private
|
|
* @var int
|
|
*/
|
|
var $compressed_size;
|
|
|
|
/**
|
|
* Minimum size of a valid gzip string
|
|
*
|
|
* @access private
|
|
* @var int
|
|
*/
|
|
var $min_compressed_size = 18;
|
|
|
|
/**
|
|
* Current position of pointer
|
|
*
|
|
* @access private
|
|
* @var int
|
|
*/
|
|
var $position = 0;
|
|
|
|
/**
|
|
* Flags (FLG)
|
|
*
|
|
* @access private
|
|
* @var int
|
|
*/
|
|
var $flags;
|
|
|
|
/**
|
|
* Uncompressed data
|
|
*
|
|
* @access public
|
|
* @see gzdecode::$compressed_data
|
|
* @var string
|
|
*/
|
|
var $data;
|
|
|
|
/**
|
|
* Modified time
|
|
*
|
|
* @access public
|
|
* @var int
|
|
*/
|
|
var $MTIME;
|
|
|
|
/**
|
|
* Extra Flags
|
|
*
|
|
* @access public
|
|
* @var int
|
|
*/
|
|
var $XFL;
|
|
|
|
/**
|
|
* Operating System
|
|
*
|
|
* @access public
|
|
* @var int
|
|
*/
|
|
var $OS;
|
|
|
|
/**
|
|
* Subfield ID 1
|
|
*
|
|
* @access public
|
|
* @see gzdecode::$extra_field
|
|
* @see gzdecode::$SI2
|
|
* @var string
|
|
*/
|
|
var $SI1;
|
|
|
|
/**
|
|
* Subfield ID 2
|
|
*
|
|
* @access public
|
|
* @see gzdecode::$extra_field
|
|
* @see gzdecode::$SI1
|
|
* @var string
|
|
*/
|
|
var $SI2;
|
|
|
|
/**
|
|
* Extra field content
|
|
*
|
|
* @access public
|
|
* @see gzdecode::$SI1
|
|
* @see gzdecode::$SI2
|
|
* @var string
|
|
*/
|
|
var $extra_field;
|
|
|
|
/**
|
|
* Original filename
|
|
*
|
|
* @access public
|
|
* @var string
|
|
*/
|
|
var $filename;
|
|
|
|
/**
|
|
* Human readable comment
|
|
*
|
|
* @access public
|
|
* @var string
|
|
*/
|
|
var $comment;
|
|
|
|
/**
|
|
* Don't allow anything to be set
|
|
*
|
|
* @param string $name
|
|
* @param mixed $value
|
|
*/
|
|
public function __set($name, $value)
|
|
{
|
|
trigger_error("Cannot write property $name", E_USER_ERROR);
|
|
}
|
|
|
|
/**
|
|
* Set the compressed string and related properties
|
|
*
|
|
* @param string $data
|
|
*/
|
|
public function __construct($data)
|
|
{
|
|
$this->compressed_data = $data;
|
|
$this->compressed_size = strlen($data);
|
|
}
|
|
|
|
/**
|
|
* Decode the GZIP stream
|
|
*
|
|
* @return bool Successfulness
|
|
*/
|
|
public function parse()
|
|
{
|
|
if ($this->compressed_size >= $this->min_compressed_size)
|
|
{
|
|
// Check ID1, ID2, and CM
|
|
if (substr($this->compressed_data, 0, 3) !== "\x1F\x8B\x08")
|
|
{
|
|
return false;
|
|
}
|
|
|
|
// Get the FLG (FLaGs)
|
|
$this->flags = ord($this->compressed_data[3]);
|
|
|
|
// FLG bits above (1 << 4) are reserved
|
|
if ($this->flags > 0x1F)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
// Advance the pointer after the above
|
|
$this->position += 4;
|
|
|
|
// MTIME
|
|
$mtime = substr($this->compressed_data, $this->position, 4);
|
|
// Reverse the string if we're on a big-endian arch because l is the only signed long and is machine endianness
|
|
if (current(unpack('S', "\x00\x01")) === 1)
|
|
{
|
|
$mtime = strrev($mtime);
|
|
}
|
|
$this->MTIME = current(unpack('l', $mtime));
|
|
$this->position += 4;
|
|
|
|
// Get the XFL (eXtra FLags)
|
|
$this->XFL = ord($this->compressed_data[$this->position++]);
|
|
|
|
// Get the OS (Operating System)
|
|
$this->OS = ord($this->compressed_data[$this->position++]);
|
|
|
|
// Parse the FEXTRA
|
|
if ($this->flags & 4)
|
|
{
|
|
// Read subfield IDs
|
|
$this->SI1 = $this->compressed_data[$this->position++];
|
|
$this->SI2 = $this->compressed_data[$this->position++];
|
|
|
|
// SI2 set to zero is reserved for future use
|
|
if ($this->SI2 === "\x00")
|
|
{
|
|
return false;
|
|
}
|
|
|
|
// Get the length of the extra field
|
|
$len = current(unpack('v', substr($this->compressed_data, $this->position, 2)));
|
|
$this->position += 2;
|
|
|
|
// Check the length of the string is still valid
|
|
$this->min_compressed_size += $len + 4;
|
|
if ($this->compressed_size >= $this->min_compressed_size)
|
|
{
|
|
// Set the extra field to the given data
|
|
$this->extra_field = substr($this->compressed_data, $this->position, $len);
|
|
$this->position += $len;
|
|
}
|
|
else
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
// Parse the FNAME
|
|
if ($this->flags & 8)
|
|
{
|
|
// Get the length of the filename
|
|
$len = strcspn($this->compressed_data, "\x00", $this->position);
|
|
|
|
// Check the length of the string is still valid
|
|
$this->min_compressed_size += $len + 1;
|
|
if ($this->compressed_size >= $this->min_compressed_size)
|
|
{
|
|
// Set the original filename to the given string
|
|
$this->filename = substr($this->compressed_data, $this->position, $len);
|
|
$this->position += $len + 1;
|
|
}
|
|
else
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
// Parse the FCOMMENT
|
|
if ($this->flags & 16)
|
|
{
|
|
// Get the length of the comment
|
|
$len = strcspn($this->compressed_data, "\x00", $this->position);
|
|
|
|
// Check the length of the string is still valid
|
|
$this->min_compressed_size += $len + 1;
|
|
if ($this->compressed_size >= $this->min_compressed_size)
|
|
{
|
|
// Set the original comment to the given string
|
|
$this->comment = substr($this->compressed_data, $this->position, $len);
|
|
$this->position += $len + 1;
|
|
}
|
|
else
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
// Parse the FHCRC
|
|
if ($this->flags & 2)
|
|
{
|
|
// Check the length of the string is still valid
|
|
$this->min_compressed_size += $len + 2;
|
|
if ($this->compressed_size >= $this->min_compressed_size)
|
|
{
|
|
// Read the CRC
|
|
$crc = current(unpack('v', substr($this->compressed_data, $this->position, 2)));
|
|
|
|
// Check the CRC matches
|
|
if ((crc32(substr($this->compressed_data, 0, $this->position)) & 0xFFFF) === $crc)
|
|
{
|
|
$this->position += 2;
|
|
}
|
|
else
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
|
|
// Decompress the actual data
|
|
if (($this->data = gzinflate(substr($this->compressed_data, $this->position, -8))) === false)
|
|
{
|
|
return false;
|
|
}
|
|
else
|
|
{
|
|
$this->position = $this->compressed_size - 8;
|
|
}
|
|
|
|
// Check CRC of data
|
|
$crc = current(unpack('V', substr($this->compressed_data, $this->position, 4)));
|
|
$this->position += 4;
|
|
/*if (extension_loaded('hash') && sprintf('%u', current(unpack('V', hash('crc32b', $this->data)))) !== sprintf('%u', $crc))
|
|
{
|
|
return false;
|
|
}*/
|
|
|
|
// Check ISIZE of data
|
|
$isize = current(unpack('V', substr($this->compressed_data, $this->position, 4)));
|
|
$this->position += 4;
|
|
if (sprintf('%u', strlen($this->data) & 0xFFFFFFFF) !== sprintf('%u', $isize))
|
|
{
|
|
return false;
|
|
}
|
|
|
|
// Wow, against all odds, we've actually got a valid gzip string
|
|
return true;
|
|
}
|
|
else
|
|
{
|
|
return false;
|
|
}
|
|
}
|
|
}
|