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See Release Notes

  • Bug fixes for general core bugs in 3.11.x will end 14 Nov 2022 (12 months plus 6 months extension).
  • Bug fixes for security issues in 3.11.x will end 13 Nov 2023 (18 months plus 12 months extension).
  • PHP version: minimum PHP 7.3.0 Note: minimum PHP version has increased since Moodle 3.10. PHP 7.4.x is supported too.
<?php
declare(strict_types=1);

namespace ZipStream;

use Psr\Http\Message\StreamInterface;
> use RuntimeException;
use ZipStream\Exception\EncodingException; use ZipStream\Exception\FileNotFoundException; use ZipStream\Exception\FileNotReadableException; use ZipStream\Exception\OverflowException; use ZipStream\Option\File as FileOptions; use ZipStream\Option\Method; use ZipStream\Option\Version; class File { const HASH_ALGORITHM = 'crc32b'; const BIT_ZERO_HEADER = 0x0008; const BIT_EFS_UTF8 = 0x0800; const COMPUTE = 1; const SEND = 2; private const CHUNKED_READ_BLOCK_SIZE = 1048576; /** * @var string */ public $name; /** * @var FileOptions */ public $opt; /** * @var Bigint */ public $len; /** * @var Bigint */ public $zlen; /** @var int */ public $crc; /** * @var Bigint */ public $hlen; /** * @var Bigint */ public $ofs; /** * @var int */ public $bits; /** * @var Version */ public $version; /** * @var ZipStream */ public $zip; /** * @var resource */ private $deflate;
>
/**
< * @var resource
> * @var \HashContext
*/ private $hash; /** * @var Method */ private $method; /** * @var Bigint */ private $totalLength; public function __construct(ZipStream $zip, string $name, ?FileOptions $opt = null) { $this->zip = $zip; $this->name = $name; $this->opt = $opt ?: new FileOptions(); $this->method = $this->opt->getMethod(); $this->version = Version::STORE(); $this->ofs = new Bigint(); } public function processPath(string $path): void { if (!is_readable($path)) { if (!file_exists($path)) { throw new FileNotFoundException($path); } throw new FileNotReadableException($path); } if ($this->zip->isLargeFile($path) === false) { $data = file_get_contents($path); $this->processData($data); } else { $this->method = $this->zip->opt->getLargeFileMethod(); $stream = new DeflateStream(fopen($path, 'rb')); $this->processStream($stream); $stream->close(); } } public function processData(string $data): void { $this->len = new Bigint(strlen($data)); $this->crc = crc32($data); // compress data if needed if ($this->method->equals(Method::DEFLATE())) { $data = gzdeflate($data); } $this->zlen = new Bigint(strlen($data)); $this->addFileHeader(); $this->zip->send($data); $this->addFileFooter(); } /** * Create and send zip header for this file. * * @return void * @throws \ZipStream\Exception\EncodingException */ public function addFileHeader(): void { $name = static::filterFilename($this->name); // calculate name length $nameLength = strlen($name); // create dos timestamp $time = static::dosTime($this->opt->getTime()->getTimestamp()); $comment = $this->opt->getComment(); if (!mb_check_encoding($name, 'ASCII') || !mb_check_encoding($comment, 'ASCII')) { // Sets Bit 11: Language encoding flag (EFS). If this bit is set, // the filename and comment fields for this file // MUST be encoded using UTF-8. (see APPENDIX D) if (!mb_check_encoding($name, 'UTF-8') || !mb_check_encoding($comment, 'UTF-8')) { throw new EncodingException( 'File name and comment should use UTF-8 ' . 'if one of them does not fit into ASCII range.' ); } $this->bits |= self::BIT_EFS_UTF8; } if ($this->method->equals(Method::DEFLATE())) { $this->version = Version::DEFLATE(); } $force = (boolean)($this->bits & self::BIT_ZERO_HEADER) && $this->zip->opt->isEnableZip64(); $footer = $this->buildZip64ExtraBlock($force); // If this file will start over 4GB limit in ZIP file, // CDR record will have to use Zip64 extension to describe offset // to keep consistency we use the same value here if ($this->zip->ofs->isOver32()) { $this->version = Version::ZIP64(); } $fields = [ ['V', ZipStream::FILE_HEADER_SIGNATURE], ['v', $this->version->getValue()], // Version needed to Extract ['v', $this->bits], // General purpose bit flags - data descriptor flag set ['v', $this->method->getValue()], // Compression method ['V', $time], // Timestamp (DOS Format) ['V', $this->crc], // CRC32 of data (0 -> moved to data descriptor footer) ['V', $this->zlen->getLowFF($force)], // Length of compressed data (forced to 0xFFFFFFFF for zero header) ['V', $this->len->getLowFF($force)], // Length of original data (forced to 0xFFFFFFFF for zero header) ['v', $nameLength], // Length of filename ['v', strlen($footer)], // Extra data (see above) ]; // pack fields and calculate "total" length $header = ZipStream::packFields($fields); // print header and filename $data = $header . $name . $footer; $this->zip->send($data); // save header length $this->hlen = Bigint::init(strlen($data)); } /** * Strip characters that are not legal in Windows filenames * to prevent compatibility issues * * @param string $filename Unprocessed filename * @return string */ public static function filterFilename(string $filename): string { // strip leading slashes from file name // (fixes bug in windows archive viewer) $filename = preg_replace('/^\\/+/', '', $filename); return str_replace(['\\', ':', '*', '?', '"', '<', '>', '|'], '_', $filename); } /** * Convert a UNIX timestamp to a DOS timestamp. * * @param int $when * @return int DOS Timestamp */ final protected static function dosTime(int $when): int { // get date array for timestamp $d = getdate($when); // set lower-bound on dates if ($d['year'] < 1980) { $d = array( 'year' => 1980, 'mon' => 1, 'mday' => 1, 'hours' => 0, 'minutes' => 0, 'seconds' => 0 ); } // remove extra years from 1980 $d['year'] -= 1980; // return date string return ($d['year'] << 25) | ($d['mon'] << 21) | ($d['mday'] << 16) | ($d['hours'] << 11) | ($d['minutes'] << 5) | ($d['seconds'] >> 1); } protected function buildZip64ExtraBlock(bool $force = false): string { $fields = []; if ($this->len->isOver32($force)) { $fields[] = ['P', $this->len]; // Length of original data } if ($this->len->isOver32($force)) { $fields[] = ['P', $this->zlen]; // Length of compressed data } if ($this->ofs->isOver32()) { $fields[] = ['P', $this->ofs]; // Offset of local header record } if (!empty($fields)) { if (!$this->zip->opt->isEnableZip64()) { throw new OverflowException(); } array_unshift( $fields, ['v', 0x0001], // 64 bit extension ['v', count($fields) * 8] // Length of data block ); $this->version = Version::ZIP64(); }
> if ($this->bits & self::BIT_EFS_UTF8) { return ZipStream::packFields($fields); > // Put the tricky entry to } > // force Linux unzip to lookup EFS flag. > $fields[] = ['v', 0x5653]; // Choose 'ZS' for proprietary usage /** > $fields[] = ['v', 0x0000]; // zero length * Create and send data descriptor footer for this file. > } * >
* @return void */ public function addFileFooter(): void { if ($this->bits & self::BIT_ZERO_HEADER) { // compressed and uncompressed size $sizeFormat = 'V'; if ($this->zip->opt->isEnableZip64()) { $sizeFormat = 'P'; } $fields = [ ['V', ZipStream::DATA_DESCRIPTOR_SIGNATURE], ['V', $this->crc], // CRC32 [$sizeFormat, $this->zlen], // Length of compressed data [$sizeFormat, $this->len], // Length of original data ]; $footer = ZipStream::packFields($fields); $this->zip->send($footer); } else { $footer = ''; } $this->totalLength = $this->hlen->add($this->zlen)->add(Bigint::init(strlen($footer))); $this->zip->addToCdr($this); } public function processStream(StreamInterface $stream): void { $this->zlen = new Bigint(); $this->len = new Bigint(); if ($this->zip->opt->isZeroHeader()) { $this->processStreamWithZeroHeader($stream); } else { $this->processStreamWithComputedHeader($stream); } } protected function processStreamWithZeroHeader(StreamInterface $stream): void { $this->bits |= self::BIT_ZERO_HEADER; $this->addFileHeader(); $this->readStream($stream, self::COMPUTE | self::SEND); $this->addFileFooter(); } protected function readStream(StreamInterface $stream, ?int $options = null): void { $this->deflateInit(); $total = 0; $size = $this->opt->getSize(); while (!$stream->eof() && ($size === 0 || $total < $size)) { $data = $stream->read(self::CHUNKED_READ_BLOCK_SIZE); $total += strlen($data); if ($size > 0 && $total > $size) { $data = substr($data, 0 , strlen($data)-($total - $size)); } $this->deflateData($stream, $data, $options); if ($options & self::SEND) { $this->zip->send($data); } } $this->deflateFinish($options); } protected function deflateInit(): void {
< $this->hash = hash_init(self::HASH_ALGORITHM);
> $hash = hash_init(self::HASH_ALGORITHM); > $this->hash = $hash;
if ($this->method->equals(Method::DEFLATE())) { $this->deflate = deflate_init( ZLIB_ENCODING_RAW, ['level' => $this->opt->getDeflateLevel()] ); } } protected function deflateData(StreamInterface $stream, string &$data, ?int $options = null): void { if ($options & self::COMPUTE) { $this->len = $this->len->add(Bigint::init(strlen($data))); hash_update($this->hash, $data); } if ($this->deflate) { $data = deflate_add( $this->deflate, $data, $stream->eof() ? ZLIB_FINISH : ZLIB_NO_FLUSH ); } if ($options & self::COMPUTE) { $this->zlen = $this->zlen->add(Bigint::init(strlen($data))); } } protected function deflateFinish(?int $options = null): void { if ($options & self::COMPUTE) { $this->crc = hexdec(hash_final($this->hash)); } } protected function processStreamWithComputedHeader(StreamInterface $stream): void { $this->readStream($stream, self::COMPUTE); $stream->rewind(); // incremental compression with deflate_add // makes this second read unnecessary // but it is only available from PHP 7.0 if (!$this->deflate && $stream instanceof DeflateStream && $this->method->equals(Method::DEFLATE())) { $stream->addDeflateFilter($this->opt); $this->zlen = new Bigint(); while (!$stream->eof()) { $data = $stream->read(self::CHUNKED_READ_BLOCK_SIZE); $this->zlen = $this->zlen->add(Bigint::init(strlen($data))); } $stream->rewind(); } $this->addFileHeader(); $this->readStream($stream, self::SEND); $this->addFileFooter(); } /** * Send CDR record for specified file. * * @return string */ public function getCdrFile(): string { $name = static::filterFilename($this->name); // get attributes $comment = $this->opt->getComment(); // get dos timestamp $time = static::dosTime($this->opt->getTime()->getTimestamp()); $footer = $this->buildZip64ExtraBlock(); $fields = [ ['V', ZipStream::CDR_FILE_SIGNATURE], // Central file header signature ['v', ZipStream::ZIP_VERSION_MADE_BY], // Made by version ['v', $this->version->getValue()], // Extract by version ['v', $this->bits], // General purpose bit flags - data descriptor flag set ['v', $this->method->getValue()], // Compression method ['V', $time], // Timestamp (DOS Format) ['V', $this->crc], // CRC32 ['V', $this->zlen->getLowFF()], // Compressed Data Length ['V', $this->len->getLowFF()], // Original Data Length ['v', strlen($name)], // Length of filename ['v', strlen($footer)], // Extra data len (see above) ['v', strlen($comment)], // Length of comment ['v', 0], // Disk number ['v', 0], // Internal File Attributes ['V', 32], // External File Attributes ['V', $this->ofs->getLowFF()] // Relative offset of local header ]; // pack fields, then append name and comment $header = ZipStream::packFields($fields); return $header . $name . $footer . $comment; } /** * @return Bigint */ public function getTotalLength(): Bigint { return $this->totalLength; } }