diff options
Diffstat (limited to 'vendor/simplepie/simplepie/src/Gzdecode.php')
| -rw-r--r-- | vendor/simplepie/simplepie/src/Gzdecode.php | 306 |
1 files changed, 297 insertions, 9 deletions
diff --git a/vendor/simplepie/simplepie/src/Gzdecode.php b/vendor/simplepie/simplepie/src/Gzdecode.php index 503e52126..786125e0b 100644 --- a/vendor/simplepie/simplepie/src/Gzdecode.php +++ b/vendor/simplepie/simplepie/src/Gzdecode.php @@ -5,10 +5,7 @@ * A PHP-Based RSS and Atom Feed Framework. * Takes the hard work out of managing a complete RSS/Atom solution. * - * Please note: This file is automatically generated by a build script. The - * full original source is always available from http://simplepie.org/ - * - * Copyright (c) 2004-2016, Ryan Parman, Sam Sneddon, Ryan McCue, and contributors + * Copyright (c) 2004-2022, Ryan Parman, Sam Sneddon, Ryan McCue, and contributors * All rights reserved. * * Redistribution and use in source and binary forms, with or without modification, are @@ -46,10 +43,301 @@ namespace SimplePie; -class_exists('SimplePie_gzdecode'); +/** + * Decode 'gzip' encoded HTTP data + * + * @package SimplePie + * @subpackage HTTP + * @link http://www.gzip.org/format.txt + */ +class Gzdecode +{ + /** + * Compressed data + * + * @access private + * @var string + * @see gzdecode::$data + */ + public $compressed_data; + + /** + * Size of compressed data + * + * @access private + * @var int + */ + public $compressed_size; + + /** + * Minimum size of a valid gzip string + * + * @access private + * @var int + */ + public $min_compressed_size = 18; + + /** + * Current position of pointer + * + * @access private + * @var int + */ + public $position = 0; + + /** + * Flags (FLG) + * + * @access private + * @var int + */ + public $flags; + + /** + * Uncompressed data + * + * @access public + * @see gzdecode::$compressed_data + * @var string + */ + public $data; + + /** + * Modified time + * + * @access public + * @var int + */ + public $MTIME; + + /** + * Extra Flags + * + * @access public + * @var int + */ + public $XFL; + + /** + * Operating System + * + * @access public + * @var int + */ + public $OS; + + /** + * Subfield ID 1 + * + * @access public + * @see gzdecode::$extra_field + * @see gzdecode::$SI2 + * @var string + */ + public $SI1; + + /** + * Subfield ID 2 + * + * @access public + * @see gzdecode::$extra_field + * @see gzdecode::$SI1 + * @var string + */ + public $SI2; + + /** + * Extra field content + * + * @access public + * @see gzdecode::$SI1 + * @see gzdecode::$SI2 + * @var string + */ + public $extra_field; + + /** + * Original filename + * + * @access public + * @var string + */ + public $filename; + + /** + * Human readable comment + * + * @access public + * @var string + */ + public $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]); -if (\false) { - class Gzdecode extends \SimplePie_gzdecode - { - } + // 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; + } + + $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; + } + + return false; + } } + +class_alias('SimplePie\Gzdecode', 'SimplePie_gzdecode'); |