[github/wallabag/wallabag.git] / inc / 3rdparty / libraries / simplepie / library / SimplePie / gzdecode.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;
		}
	}
}
Commit	Line	Data
ec397236 NL	1	<?php
	2	/**
	3	* SimplePie
	4	*
	5	* A PHP-Based RSS and Atom Feed Framework.
	6	* Takes the hard work out of managing a complete RSS/Atom solution.
	7	*
42c80841	8	* Copyright (c) 2004-2012, Ryan Parman, Geoffrey Sneddon, Ryan McCue, and contributors
ec397236 NL	9	* All rights reserved.
	10	*
	11	* Redistribution and use in source and binary forms, with or without modification, are
	12	* permitted provided that the following conditions are met:
	13	*
	14	* * Redistributions of source code must retain the above copyright notice, this list of
	15	* conditions and the following disclaimer.
	16	*
	17	* * Redistributions in binary form must reproduce the above copyright notice, this list
	18	* of conditions and the following disclaimer in the documentation and/or other materials
	19	* provided with the distribution.
	20	*
	21	* * Neither the name of the SimplePie Team nor the names of its contributors may be used
	22	* to endorse or promote products derived from this software without specific prior
	23	* written permission.
	24	*
	25	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS
	26	* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
	27	* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS
	28	* AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	29	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
	30	* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	31	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
	32	* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	33	* POSSIBILITY OF SUCH DAMAGE.
	34	*
	35	* @package SimplePie
42c80841 NL	36	* @version 1.3.1
42c80841 NL	37	* @copyright 2004-2012 Ryan Parman, Geoffrey Sneddon, Ryan McCue
ec397236 NL	38	* @author Ryan Parman
	39	* @author Geoffrey Sneddon
	40	* @author Ryan McCue
	41	* @link http://simplepie.org/ SimplePie
	42	* @license http://www.opensource.org/licenses/bsd-license.php BSD License
ec397236 NL	43	*/
	44
	45
	46	/**
42c80841	47	* Decode 'gzip' encoded HTTP data
ec397236 NL	48	*
ec397236 NL	49	* @package SimplePie
42c80841 NL	50	* @subpackage HTTP
42c80841 NL	51	* @link http://www.gzip.org/format.txt
ec397236 NL	52	*/
	53	class SimplePie_gzdecode
	54	{
	55	/**
	56	* Compressed data
	57	*
	58	* @access private
42c80841	59	* @var string
ec397236 NL	60	* @see gzdecode::$data
	61	*/
	62	var $compressed_data;
	63
	64	/**
	65	* Size of compressed data
	66	*
	67	* @access private
42c80841	68	* @var int
ec397236 NL	69	*/
	70	var $compressed_size;
	71
	72	/**
	73	* Minimum size of a valid gzip string
	74	*
	75	* @access private
42c80841	76	* @var int
ec397236 NL	77	*/
	78	var $min_compressed_size = 18;
	79
	80	/**
	81	* Current position of pointer
	82	*
	83	* @access private
42c80841	84	* @var int
ec397236 NL	85	*/
	86	var $position = 0;
	87
	88	/**
	89	* Flags (FLG)
	90	*
	91	* @access private
42c80841	92	* @var int
ec397236 NL	93	*/
	94	var $flags;
	95
	96	/**
	97	* Uncompressed data
	98	*
	99	* @access public
	100	* @see gzdecode::$compressed_data
42c80841	101	* @var string
ec397236 NL	102	*/
	103	var $data;
	104
	105	/**
	106	* Modified time
	107	*
	108	* @access public
42c80841	109	* @var int
ec397236 NL	110	*/
	111	var $MTIME;
	112
	113	/**
	114	* Extra Flags
	115	*
	116	* @access public
42c80841	117	* @var int
ec397236 NL	118	*/
	119	var $XFL;
	120
	121	/**
	122	* Operating System
	123	*
	124	* @access public
42c80841	125	* @var int
ec397236 NL	126	*/
	127	var $OS;
	128
	129	/**
	130	* Subfield ID 1
	131	*
	132	* @access public
	133	* @see gzdecode::$extra_field
	134	* @see gzdecode::$SI2
42c80841	135	* @var string
ec397236 NL	136	*/
	137	var $SI1;
	138
	139	/**
	140	* Subfield ID 2
	141	*
	142	* @access public
	143	* @see gzdecode::$extra_field
	144	* @see gzdecode::$SI1
42c80841	145	* @var string
ec397236 NL	146	*/
	147	var $SI2;
	148
	149	/**
	150	* Extra field content
	151	*
	152	* @access public
	153	* @see gzdecode::$SI1
	154	* @see gzdecode::$SI2
42c80841	155	* @var string
ec397236 NL	156	*/
	157	var $extra_field;
	158
	159	/**
	160	* Original filename
	161	*
	162	* @access public
42c80841	163	* @var string
ec397236 NL	164	*/
	165	var $filename;
	166
	167	/**
	168	* Human readable comment
	169	*
	170	* @access public
42c80841	171	* @var string
ec397236 NL	172	*/
	173	var $comment;
	174
	175	/**
	176	* Don't allow anything to be set
	177	*
42c80841 NL	178	* @param string $name
42c80841 NL	179	* @param mixed $value
ec397236 NL	180	*/
	181	public function __set($name, $value)
	182	{
	183	trigger_error("Cannot write property $name", E_USER_ERROR);
	184	}
	185
	186	/**
	187	* Set the compressed string and related properties
	188	*
42c80841	189	* @param string $data
ec397236 NL	190	*/
	191	public function __construct($data)
	192	{
	193	$this->compressed_data = $data;
	194	$this->compressed_size = strlen($data);
	195	}
	196
	197	/**
	198	* Decode the GZIP stream
	199	*
42c80841	200	* @return bool Successfulness
ec397236 NL	201	*/
	202	public function parse()
	203	{
	204	if ($this->compressed_size >= $this->min_compressed_size)
	205	{
	206	// Check ID1, ID2, and CM
	207	if (substr($this->compressed_data, 0, 3) !== "\x1F\x8B\x08")
	208	{
	209	return false;
	210	}
	211
	212	// Get the FLG (FLaGs)
	213	$this->flags = ord($this->compressed_data[3]);
	214
	215	// FLG bits above (1 << 4) are reserved
	216	if ($this->flags > 0x1F)
	217	{
	218	return false;
	219	}
	220
	221	// Advance the pointer after the above
	222	$this->position += 4;
	223
	224	// MTIME
	225	$mtime = substr($this->compressed_data, $this->position, 4);
	226	// Reverse the string if we're on a big-endian arch because l is the only signed long and is machine endianness
	227	if (current(unpack('S', "\x00\x01")) === 1)
	228	{
	229	$mtime = strrev($mtime);
	230	}
	231	$this->MTIME = current(unpack('l', $mtime));
	232	$this->position += 4;
	233
	234	// Get the XFL (eXtra FLags)
	235	$this->XFL = ord($this->compressed_data[$this->position++]);
	236
	237	// Get the OS (Operating System)
	238	$this->OS = ord($this->compressed_data[$this->position++]);
	239
	240	// Parse the FEXTRA
	241	if ($this->flags & 4)
	242	{
	243	// Read subfield IDs
	244	$this->SI1 = $this->compressed_data[$this->position++];
	245	$this->SI2 = $this->compressed_data[$this->position++];
	246
	247	// SI2 set to zero is reserved for future use
	248	if ($this->SI2 === "\x00")
	249	{
	250	return false;
	251	}
	252
	253	// Get the length of the extra field
	254	$len = current(unpack('v', substr($this->compressed_data, $this->position, 2)));
	255	$this->position += 2;
	256
	257	// Check the length of the string is still valid
	258	$this->min_compressed_size += $len + 4;
	259	if ($this->compressed_size >= $this->min_compressed_size)
	260	{
	261	// Set the extra field to the given data
	262	$this->extra_field = substr($this->compressed_data, $this->position, $len);
	263	$this->position += $len;
	264	}
265	else
266	{
267	return false;
268	}
269	}
270
271	// Parse the FNAME
272	if ($this->flags & 8)
273	{
274	// Get the length of the filename
275	$len = strcspn($this->compressed_data, "\x00", $this->position);
276
277	// Check the length of the string is still valid
278	$this->min_compressed_size += $len + 1;
279	if ($this->compressed_size >= $this->min_compressed_size)
280	{
281	// Set the original filename to the given string
282	$this->filename = substr($this->compressed_data, $this->position, $len);
283	$this->position += $len + 1;
284	}
285	else
286	{
287	return false;
288	}
289	}
290
291	// Parse the FCOMMENT
292	if ($this->flags & 16)
293	{
294	// Get the length of the comment
295	$len = strcspn($this->compressed_data, "\x00", $this->position);
296
297	// Check the length of the string is still valid
298	$this->min_compressed_size += $len + 1;
299	if ($this->compressed_size >= $this->min_compressed_size)
300	{
301	// Set the original comment to the given string
302	$this->comment = substr($this->compressed_data, $this->position, $len);
303	$this->position += $len + 1;
304	}
305	else
306	{
307	return false;
308	}
309	}
310
311	// Parse the FHCRC
312	if ($this->flags & 2)
313	{
314	// Check the length of the string is still valid
315	$this->min_compressed_size += $len + 2;
316	if ($this->compressed_size >= $this->min_compressed_size)
317	{
318	// Read the CRC
319	$crc = current(unpack('v', substr($this->compressed_data, $this->position, 2)));
320
321	// Check the CRC matches
322	if ((crc32(substr($this->compressed_data, 0, $this->position)) & 0xFFFF) === $crc)
323	{
324	$this->position += 2;
325	}
326	else
327	{
328	return false;
329	}
330	}
331	else
332	{
333	return false;
334	}
335	}
336
337	// Decompress the actual data
338	if (($this->data = gzinflate(substr($this->compressed_data, $this->position, -8))) === false)
339	{
340	return false;
341	}
342	else
343	{
344	$this->position = $this->compressed_size - 8;
345	}
346
347	// Check CRC of data
348	$crc = current(unpack('V', substr($this->compressed_data, $this->position, 4)));
349	$this->position += 4;
350	/*if (extension_loaded('hash') && sprintf('%u', current(unpack('V', hash('crc32b', $this->data)))) !== sprintf('%u', $crc))
351	{
352	return false;
353	}*/
354
355	// Check ISIZE of data
356	$isize = current(unpack('V', substr($this->compressed_data, $this->position, 4)));
357	$this->position += 4;
358	if (sprintf('%u', strlen($this->data) & 0xFFFFFFFF) !== sprintf('%u', $isize))
359	{
360	return false;
361	}
362
363	// Wow, against all odds, we've actually got a valid gzip string
364	return true;
365	}
366	else
367	{
368	return false;
369	}
370	}
371	}