%PDF-
%PDF-
Mini Shell
Mini Shell
<?php
/**
* Simulation of Microsoft Internet Explorer's MIME type detection algorithm.
*
* @file
* @todo Define the exact license of this file.
*/
/**
* This class simulates Microsoft Internet Explorer's terribly broken and
* insecure MIME type detection algorithm. It can be used to check web uploads
* with an apparently safe type, to see if IE will reinterpret them to produce
* something dangerous.
*
* It is full of bugs and strange design choices should not under any
* circumstances be used to determine a MIME type to present to a user or
* client. (Apple Safari developers, this means you too.)
*
* This class is based on a disassembly of IE 5.0, 6.0 and 7.0. Although I have
* attempted to ensure that this code works in exactly the same way as Internet
* Explorer, it does not share any source code, or creative choices such as
* variable names, thus I (Tim Starling) claim copyright on it.
*
* It may be redistributed without restriction. To aid reuse, this class does
* not depend on any MediaWiki module.
*/
class IEContentAnalyzer {
/**
* Relevant data taken from the type table in IE 5
*/
protected $baseTypeTable = [
'ambiguous' /*1*/ => [
'text/plain',
'application/octet-stream',
'application/x-netcdf', // [sic]
],
'text' /*3*/ => [
'text/richtext', 'image/x-bitmap', 'application/postscript', 'application/base64',
'application/macbinhex40', 'application/x-cdf', 'text/scriptlet'
],
'binary' /*4*/ => [
'application/pdf', 'audio/x-aiff', 'audio/basic', 'audio/wav', 'image/gif',
'image/pjpeg', 'image/jpeg', 'image/tiff', 'image/x-png', 'image/png', 'image/bmp',
'image/x-jg', 'image/x-art', 'image/x-emf', 'image/x-wmf', 'video/avi',
'video/x-msvideo', 'video/mpeg', 'application/x-compressed',
'application/x-zip-compressed', 'application/x-gzip-compressed', 'application/java',
'application/x-msdownload'
],
'html' /*5*/ => [ 'text/html' ],
];
/**
* Changes to the type table in later versions of IE
*/
protected $addedTypes = [
'ie07' => [
'text' => [ 'text/xml', 'application/xml' ]
],
];
/**
* An approximation of the "Content Type" values in HKEY_CLASSES_ROOT in a
* typical Windows installation.
*
* Used for extension to MIME type mapping if detection fails.
*/
protected $registry = [
'.323' => 'text/h323',
'.3g2' => 'video/3gpp2',
'.3gp' => 'video/3gpp',
'.3gp2' => 'video/3gpp2',
'.3gpp' => 'video/3gpp',
'.aac' => 'audio/aac',
'.ac3' => 'audio/ac3',
'.accda' => 'application/msaccess',
'.accdb' => 'application/msaccess',
'.accdc' => 'application/msaccess',
'.accde' => 'application/msaccess',
'.accdr' => 'application/msaccess',
'.accdt' => 'application/msaccess',
'.ade' => 'application/msaccess',
'.adp' => 'application/msaccess',
'.adts' => 'audio/aac',
'.ai' => 'application/postscript',
'.aif' => 'audio/aiff',
'.aifc' => 'audio/aiff',
'.aiff' => 'audio/aiff',
'.amc' => 'application/x-mpeg',
'.application' => 'application/x-ms-application',
'.asf' => 'video/x-ms-asf',
'.asx' => 'video/x-ms-asf',
'.au' => 'audio/basic',
'.avi' => 'video/avi',
'.bmp' => 'image/bmp',
'.caf' => 'audio/x-caf',
'.cat' => 'application/vnd.ms-pki.seccat',
'.cbo' => 'application/sha',
'.cdda' => 'audio/aiff',
'.cer' => 'application/x-x509-ca-cert',
'.conf' => 'text/plain',
'.crl' => 'application/pkix-crl',
'.crt' => 'application/x-x509-ca-cert',
'.css' => 'text/css',
'.csv' => 'application/vnd.ms-excel',
'.der' => 'application/x-x509-ca-cert',
'.dib' => 'image/bmp',
'.dif' => 'video/x-dv',
'.dll' => 'application/x-msdownload',
'.doc' => 'application/msword',
'.docm' => 'application/vnd.ms-word.document.macroEnabled.12',
'.docx' => 'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
'.dot' => 'application/msword',
'.dotm' => 'application/vnd.ms-word.template.macroEnabled.12',
'.dotx' => 'application/vnd.openxmlformats-officedocument.wordprocessingml.template',
'.dv' => 'video/x-dv',
'.dwfx' => 'model/vnd.dwfx+xps',
'.edn' => 'application/vnd.adobe.edn',
'.eml' => 'message/rfc822',
'.eps' => 'application/postscript',
'.etd' => 'application/x-ebx',
'.exe' => 'application/x-msdownload',
'.fdf' => 'application/vnd.fdf',
'.fif' => 'application/fractals',
'.gif' => 'image/gif',
'.gsm' => 'audio/x-gsm',
'.hqx' => 'application/mac-binhex40',
'.hta' => 'application/hta',
'.htc' => 'text/x-component',
'.htm' => 'text/html',
'.html' => 'text/html',
'.htt' => 'text/webviewhtml',
'.hxa' => 'application/xml',
'.hxc' => 'application/xml',
'.hxd' => 'application/octet-stream',
'.hxe' => 'application/xml',
'.hxf' => 'application/xml',
'.hxh' => 'application/octet-stream',
'.hxi' => 'application/octet-stream',
'.hxk' => 'application/xml',
'.hxq' => 'application/octet-stream',
'.hxr' => 'application/octet-stream',
'.hxs' => 'application/octet-stream',
'.hxt' => 'application/xml',
'.hxv' => 'application/xml',
'.hxw' => 'application/octet-stream',
'.ico' => 'image/x-icon',
'.iii' => 'application/x-iphone',
'.ins' => 'application/x-internet-signup',
'.iqy' => 'text/x-ms-iqy',
'.isp' => 'application/x-internet-signup',
'.jfif' => 'image/jpeg',
'.jnlp' => 'application/x-java-jnlp-file',
'.jpe' => 'image/jpeg',
'.jpeg' => 'image/jpeg',
'.jpg' => 'image/jpeg',
'.jtx' => 'application/x-jtx+xps',
'.latex' => 'application/x-latex',
'.log' => 'text/plain',
'.m1v' => 'video/mpeg',
'.m2v' => 'video/mpeg',
'.m3u' => 'audio/x-mpegurl',
'.mac' => 'image/x-macpaint',
'.man' => 'application/x-troff-man',
'.mda' => 'application/msaccess',
'.mdb' => 'application/msaccess',
'.mde' => 'application/msaccess',
'.mfp' => 'application/x-shockwave-flash',
'.mht' => 'message/rfc822',
'.mhtml' => 'message/rfc822',
'.mid' => 'audio/mid',
'.midi' => 'audio/mid',
'.mod' => 'video/mpeg',
'.mov' => 'video/quicktime',
'.mp2' => 'video/mpeg',
'.mp2v' => 'video/mpeg',
'.mp3' => 'audio/mpeg',
'.mp4' => 'video/mp4',
'.mpa' => 'video/mpeg',
'.mpe' => 'video/mpeg',
'.mpeg' => 'video/mpeg',
'.mpf' => 'application/vnd.ms-mediapackage',
'.mpg' => 'video/mpeg',
'.mpv2' => 'video/mpeg',
'.mqv' => 'video/quicktime',
'.NMW' => 'application/nmwb',
'.nws' => 'message/rfc822',
'.odc' => 'text/x-ms-odc',
'.ols' => 'application/vnd.ms-publisher',
'.p10' => 'application/pkcs10',
'.p12' => 'application/x-pkcs12',
'.p7b' => 'application/x-pkcs7-certificates',
'.p7c' => 'application/pkcs7-mime',
'.p7m' => 'application/pkcs7-mime',
'.p7r' => 'application/x-pkcs7-certreqresp',
'.p7s' => 'application/pkcs7-signature',
'.pct' => 'image/pict',
'.pdf' => 'application/pdf',
'.pdx' => 'application/vnd.adobe.pdx',
'.pfx' => 'application/x-pkcs12',
'.pic' => 'image/pict',
'.pict' => 'image/pict',
'.pinstall' => 'application/x-picasa-detect',
'.pko' => 'application/vnd.ms-pki.pko',
'.png' => 'image/png',
'.pnt' => 'image/x-macpaint',
'.pntg' => 'image/x-macpaint',
'.pot' => 'application/vnd.ms-powerpoint',
'.potm' => 'application/vnd.ms-powerpoint.template.macroEnabled.12',
'.potx' => 'application/vnd.openxmlformats-officedocument.presentationml.template',
'.ppa' => 'application/vnd.ms-powerpoint',
'.ppam' => 'application/vnd.ms-powerpoint.addin.macroEnabled.12',
'.pps' => 'application/vnd.ms-powerpoint',
'.ppsm' => 'application/vnd.ms-powerpoint.slideshow.macroEnabled.12',
'.ppsx' => 'application/vnd.openxmlformats-officedocument.presentationml.slideshow',
'.ppt' => 'application/vnd.ms-powerpoint',
'.pptm' => 'application/vnd.ms-powerpoint.presentation.macroEnabled.12',
'.pptx' => 'application/vnd.openxmlformats-officedocument.presentationml.presentation',
'.prf' => 'application/pics-rules',
'.ps' => 'application/postscript',
'.pub' => 'application/vnd.ms-publisher',
'.pwz' => 'application/vnd.ms-powerpoint',
'.py' => 'text/plain',
'.pyw' => 'text/plain',
'.qht' => 'text/x-html-insertion',
'.qhtm' => 'text/x-html-insertion',
'.qt' => 'video/quicktime',
'.qti' => 'image/x-quicktime',
'.qtif' => 'image/x-quicktime',
'.qtl' => 'application/x-quicktimeplayer',
'.rat' => 'application/rat-file',
'.rmf' => 'application/vnd.adobe.rmf',
'.rmi' => 'audio/mid',
'.rqy' => 'text/x-ms-rqy',
'.rtf' => 'application/msword',
'.sct' => 'text/scriptlet',
'.sd2' => 'audio/x-sd2',
'.sdp' => 'application/sdp',
'.shtml' => 'text/html',
'.sit' => 'application/x-stuffit',
'.sldm' => 'application/vnd.ms-powerpoint.slide.macroEnabled.12',
'.sldx' => 'application/vnd.openxmlformats-officedocument.presentationml.slide',
'.slk' => 'application/vnd.ms-excel',
'.snd' => 'audio/basic',
'.so' => 'application/x-apachemodule',
'.sol' => 'text/plain',
'.sor' => 'text/plain',
'.spc' => 'application/x-pkcs7-certificates',
'.spl' => 'application/futuresplash',
'.sst' => 'application/vnd.ms-pki.certstore',
'.stl' => 'application/vnd.ms-pki.stl',
'.swf' => 'application/x-shockwave-flash',
'.thmx' => 'application/vnd.ms-officetheme',
'.tif' => 'image/tiff',
'.tiff' => 'image/tiff',
'.txt' => 'text/plain',
'.uls' => 'text/iuls',
'.vcf' => 'text/x-vcard',
'.vdx' => 'application/vnd.ms-visio.viewer',
'.vsd' => 'application/vnd.ms-visio.viewer',
'.vss' => 'application/vnd.ms-visio.viewer',
'.vst' => 'application/vnd.ms-visio.viewer',
'.vsx' => 'application/vnd.ms-visio.viewer',
'.vtx' => 'application/vnd.ms-visio.viewer',
'.wav' => 'audio/wav',
'.wax' => 'audio/x-ms-wax',
'.wbk' => 'application/msword',
'.wdp' => 'image/vnd.ms-photo',
'.wiz' => 'application/msword',
'.wm' => 'video/x-ms-wm',
'.wma' => 'audio/x-ms-wma',
'.wmd' => 'application/x-ms-wmd',
'.wmv' => 'video/x-ms-wmv',
'.wmx' => 'video/x-ms-wmx',
'.wmz' => 'application/x-ms-wmz',
'.wpl' => 'application/vnd.ms-wpl',
'.wsc' => 'text/scriptlet',
'.wvx' => 'video/x-ms-wvx',
'.xaml' => 'application/xaml+xml',
'.xbap' => 'application/x-ms-xbap',
'.xdp' => 'application/vnd.adobe.xdp+xml',
'.xfdf' => 'application/vnd.adobe.xfdf',
'.xht' => 'application/xhtml+xml',
'.xhtml' => 'application/xhtml+xml',
'.xla' => 'application/vnd.ms-excel',
'.xlam' => 'application/vnd.ms-excel.addin.macroEnabled.12',
'.xlk' => 'application/vnd.ms-excel',
'.xll' => 'application/vnd.ms-excel',
'.xlm' => 'application/vnd.ms-excel',
'.xls' => 'application/vnd.ms-excel',
'.xlsb' => 'application/vnd.ms-excel.sheet.binary.macroEnabled.12',
'.xlsm' => 'application/vnd.ms-excel.sheet.macroEnabled.12',
'.xlsx' => 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
'.xlt' => 'application/vnd.ms-excel',
'.xltm' => 'application/vnd.ms-excel.template.macroEnabled.12',
'.xltx' => 'application/vnd.openxmlformats-officedocument.spreadsheetml.template',
'.xlw' => 'application/vnd.ms-excel',
'.xml' => 'text/xml',
'.xps' => 'application/vnd.ms-xpsdocument',
'.xsl' => 'text/xml',
];
/**
* IE versions which have been analysed to bring you this class, and for
* which some substantive difference exists. These will appear as keys
* in the return value of getRealMimesFromData(). The names are chosen to sort correctly.
*/
protected $versions = [ 'ie05', 'ie06', 'ie07', 'ie07.strict', 'ie07.nohtml' ];
/**
* Type table with versions expanded
*/
protected $typeTable = [];
/** constructor */
function __construct() {
// Construct versioned type arrays from the base type array plus additions
$types = $this->baseTypeTable;
foreach ( $this->versions as $version ) {
if ( isset( $this->addedTypes[$version] ) ) {
foreach ( $this->addedTypes[$version] as $format => $addedTypes ) {
$types[$format] = array_merge( $types[$format], $addedTypes );
}
}
$this->typeTable[$version] = $types;
}
}
/**
* Get the MIME types from getMimesFromData(), but convert the result from IE's
* idiosyncratic private types into something other apps will understand.
*
* @param string $fileName the file name (unused at present)
* @param string $chunk the first 256 bytes of the file
* @param string $proposed the MIME type proposed by the server
*
* @return array map of IE version to detected MIME type
*/
public function getRealMimesFromData( $fileName, $chunk, $proposed ) {
$types = $this->getMimesFromData( $fileName, $chunk, $proposed );
$types = array_map( [ $this, 'translateMimeType' ], $types );
return $types;
}
/**
* Translate a MIME type from IE's idiosyncratic private types into
* more commonly understood type strings
* @param string $type
* @return string
*/
public function translateMimeType( $type ) {
static $table = [
'image/pjpeg' => 'image/jpeg',
'image/x-png' => 'image/png',
'image/x-wmf' => 'application/x-msmetafile',
'image/bmp' => 'image/x-bmp',
'application/x-zip-compressed' => 'application/zip',
'application/x-compressed' => 'application/x-compress',
'application/x-gzip-compressed' => 'application/x-gzip',
'audio/mid' => 'audio/midi',
];
if ( isset( $table[$type] ) ) {
$type = $table[$type];
}
return $type;
}
/**
* Get the untranslated MIME types for all known versions
*
* @param string $fileName the file name (unused at present)
* @param string $chunk the first 256 bytes of the file
* @param string $proposed the MIME type proposed by the server
*
* @return array map of IE version to detected MIME type
*/
public function getMimesFromData( $fileName, $chunk, $proposed ) {
$types = [];
foreach ( $this->versions as $version ) {
$types[$version] = $this->getMimeTypeForVersion( $version, $fileName, $chunk, $proposed );
}
return $types;
}
/**
* Get the MIME type for a given named version
* @param string $version
* @param string $fileName
* @param string $chunk
* @param string $proposed
* @return bool|string
*/
protected function getMimeTypeForVersion( $version, $fileName, $chunk, $proposed ) {
// Strip text after a semicolon
$semiPos = strpos( $proposed, ';' );
if ( $semiPos !== false ) {
$proposed = substr( $proposed, 0, $semiPos );
}
$proposedFormat = $this->getDataFormat( $version, $proposed );
if ( $proposedFormat == 'unknown'
&& $proposed != 'multipart/mixed'
&& $proposed != 'multipart/x-mixed-replace'
) {
return $proposed;
}
if ( strval( $chunk ) === '' ) {
return $proposed;
}
// Truncate chunk at 255 bytes
$chunk = substr( $chunk, 0, 255 );
// IE does the Check*Headers() calls last, and instead does the following image
// type checks by directly looking for the magic numbers. What I do here should
// have the same effect since the magic number checks are identical in both cases.
$result = $this->sampleData( $version, $chunk );
$sampleFound = $result['found'];
$counters = $result['counters'];
$binaryType = $this->checkBinaryHeaders( $version, $chunk );
$textType = $this->checkTextHeaders( $version, $chunk );
if ( $proposed == 'text/html' && isset( $sampleFound['html'] ) ) {
return 'text/html';
}
if ( $proposed == 'image/gif' && $binaryType == 'image/gif' ) {
return 'image/gif';
}
if ( ( $proposed == 'image/pjpeg' || $proposed == 'image/jpeg' )
&& $binaryType == 'image/pjpeg'
) {
return $proposed;
}
// PNG check added in IE 7
if ( $version >= 'ie07'
&& ( $proposed == 'image/x-png' || $proposed == 'image/png' )
&& $binaryType == 'image/x-png'
) {
return $proposed;
}
// CDF was removed in IE 7 so it won't be in $sampleFound for later versions
if ( isset( $sampleFound['cdf'] ) ) {
return 'application/x-cdf';
}
// RSS and Atom were added in IE 7 so they won't be in $sampleFound for
// previous versions
if ( isset( $sampleFound['rss'] ) ) {
return 'application/rss+xml';
}
if ( isset( $sampleFound['rdf-tag'] )
&& isset( $sampleFound['rdf-url'] )
&& isset( $sampleFound['rdf-purl'] )
) {
return 'application/rss+xml';
}
if ( isset( $sampleFound['atom'] ) ) {
return 'application/atom+xml';
}
if ( isset( $sampleFound['xml'] ) ) {
// TODO: I'm not sure under what circumstances this flag is enabled
if ( strpos( $version, 'strict' ) !== false ) {
if ( $proposed == 'text/html' || $proposed == 'text/xml' ) {
return 'text/xml';
}
} else {
return 'text/xml';
}
}
if ( isset( $sampleFound['html'] ) ) {
// TODO: I'm not sure under what circumstances this flag is enabled
if ( strpos( $version, 'nohtml' ) !== false ) {
if ( $proposed == 'text/plain' ) {
return 'text/html';
}
} else {
return 'text/html';
}
}
if ( isset( $sampleFound['xbm'] ) ) {
return 'image/x-bitmap';
}
if ( isset( $sampleFound['binhex'] ) ) {
return 'application/macbinhex40';
}
if ( isset( $sampleFound['scriptlet'] ) ) {
if ( strpos( $version, 'strict' ) !== false ) {
if ( $proposed == 'text/plain' || $proposed == 'text/scriptlet' ) {
return 'text/scriptlet';
}
} else {
return 'text/scriptlet';
}
}
// Freaky heuristics to determine if the data is text or binary
// The heuristic is of course broken for non-ASCII text
if ( $counters['ctrl'] != 0 && ( $counters['ff'] + $counters['low'] )
< ( $counters['ctrl'] + $counters['high'] ) * 16
) {
$kindOfBinary = true;
$type = $binaryType ?: $textType;
if ( $type === false ) {
$type = 'application/octet-stream';
}
} else {
$kindOfBinary = false;
$type = $textType ?: $binaryType;
if ( $type === false ) {
$type = 'text/plain';
}
}
// Check if the output format is ambiguous
// This generally means that detection failed, real types aren't ambiguous
$detectedFormat = $this->getDataFormat( $version, $type );
if ( $detectedFormat != 'ambiguous' ) {
return $type;
}
if ( $proposedFormat != 'ambiguous' ) {
// FormatAgreesWithData()
if ( $proposedFormat == 'text' && !$kindOfBinary ) {
return $proposed;
}
if ( $proposedFormat == 'binary' && $kindOfBinary ) {
return $proposed;
}
if ( $proposedFormat == 'html' ) {
return $proposed;
}
}
// Find a MIME type by searching the registry for the file extension.
$dotPos = strrpos( $fileName, '.' );
if ( $dotPos === false ) {
return $type;
}
$ext = substr( $fileName, $dotPos );
if ( isset( $this->registry[$ext] ) ) {
return $this->registry[$ext];
}
// TODO: If the extension has an application registered to it, IE will return
// application/octet-stream. We'll skip that, so we could erroneously
// return text/plain or application/x-netcdf where application/octet-stream
// would be correct.
return $type;
}
/**
* Check for text headers at the start of the chunk
* Confirmed same in 5 and 7.
* @param string $version
* @param string $chunk
* @return bool|string
*/
private function checkTextHeaders( $version, $chunk ) {
$chunk2 = substr( $chunk, 0, 2 );
$chunk4 = substr( $chunk, 0, 4 );
$chunk5 = substr( $chunk, 0, 5 );
if ( $chunk4 == '%PDF' ) {
return 'application/pdf';
}
if ( $chunk2 == '%!' ) {
return 'application/postscript';
}
if ( $chunk5 == '{\\rtf' ) {
return 'text/richtext';
}
if ( $chunk5 == 'begin' ) {
return 'application/base64';
}
return false;
}
/**
* Check for binary headers at the start of the chunk
* Confirmed same in 5 and 7.
* @param string $version
* @param string $chunk
* @return bool|string
*/
private function checkBinaryHeaders( $version, $chunk ) {
$chunk2 = substr( $chunk, 0, 2 );
$chunk3 = substr( $chunk, 0, 3 );
$chunk4 = substr( $chunk, 0, 4 );
$chunk5 = substr( $chunk, 0, 5 );
$chunk5uc = strtoupper( $chunk5 );
$chunk8 = substr( $chunk, 0, 8 );
if ( $chunk5uc == 'GIF87' || $chunk5uc == 'GIF89' ) {
return 'image/gif';
}
if ( $chunk2 == "\xff\xd8" ) {
return 'image/pjpeg'; // actually plain JPEG but this is what IE returns
}
if ( $chunk2 == 'BM'
&& substr( $chunk, 6, 2 ) == "\000\000"
&& substr( $chunk, 8, 2 ) == "\000\000"
) {
return 'image/bmp'; // another non-standard MIME
}
if ( $chunk4 == 'RIFF'
&& substr( $chunk, 8, 4 ) == 'WAVE'
) {
return 'audio/wav';
}
// These were integer literals in IE
// Perhaps the author was not sure what the target endianness was
if ( $chunk4 == ".sd\000"
|| $chunk4 == ".snd"
|| $chunk4 == "\000ds."
|| $chunk4 == "dns."
) {
return 'audio/basic';
}
if ( $chunk3 == "MM\000" ) {
return 'image/tiff';
}
if ( $chunk2 == 'MZ' ) {
return 'application/x-msdownload';
}
if ( $chunk8 == "\x89PNG\x0d\x0a\x1a\x0a" ) {
return 'image/x-png'; // [sic]
}
if ( strlen( $chunk ) >= 5 ) {
$byte2 = ord( $chunk[2] );
$byte4 = ord( $chunk[4] );
if ( $byte2 >= 3 && $byte2 <= 31 && $byte4 == 0 && $chunk2 == 'JG' ) {
return 'image/x-jg';
}
}
// More endian confusion?
if ( $chunk4 == 'MROF' ) {
return 'audio/x-aiff';
}
$chunk4_8 = substr( $chunk, 8, 4 );
if ( $chunk4 == 'FORM' && ( $chunk4_8 == 'AIFF' || $chunk4_8 == 'AIFC' ) ) {
return 'audio/x-aiff';
}
if ( $chunk4 == 'RIFF' && $chunk4_8 == 'AVI ' ) {
return 'video/avi';
}
if ( $chunk4 == "\x00\x00\x01\xb3" || $chunk4 == "\x00\x00\x01\xba" ) {
return 'video/mpeg';
}
if ( $chunk4 == "\001\000\000\000"
&& substr( $chunk, 40, 4 ) == ' EMF'
) {
return 'image/x-emf';
}
if ( $chunk4 == "\xd7\xcd\xc6\x9a" ) {
return 'image/x-wmf';
}
if ( $chunk4 == "\xca\xfe\xba\xbe" ) {
return 'application/java';
}
if ( $chunk2 == 'PK' ) {
return 'application/x-zip-compressed';
}
if ( $chunk2 == "\x1f\x9d" ) {
return 'application/x-compressed';
}
if ( $chunk2 == "\x1f\x8b" ) {
return 'application/x-gzip-compressed';
}
// Skip redundant check for ZIP
if ( $chunk5 == "MThd\000" ) {
return 'audio/mid';
}
if ( $chunk4 == '%PDF' ) {
return 'application/pdf';
}
return false;
}
/**
* Do heuristic checks on the bulk of the data sample.
* Search for HTML tags.
* @param string $version
* @param string $chunk
* @return array
*/
protected function sampleData( $version, $chunk ) {
$found = [];
$counters = [
'ctrl' => 0,
'high' => 0,
'low' => 0,
'lf' => 0,
'cr' => 0,
'ff' => 0
];
$htmlTags = [
'html',
'head',
'title',
'body',
'script',
'a href',
'pre',
'img',
'plaintext',
'table'
];
$rdfUrl = 'http://www.w3.org/1999/02/22-rdf-syntax-ns#';
$rdfPurl = 'http://purl.org/rss/1.0/';
$xbmMagic1 = '#define';
$xbmMagic2 = '_width';
$xbmMagic3 = '_bits';
$binhexMagic = 'converted with BinHex';
$chunkLength = strlen( $chunk );
for ( $offset = 0; $offset < $chunkLength; $offset++ ) {
$curChar = $chunk[$offset];
if ( $curChar == "\x0a" ) {
$counters['lf']++;
continue;
} elseif ( $curChar == "\x0d" ) {
$counters['cr']++;
continue;
} elseif ( $curChar == "\x0c" ) {
$counters['ff']++;
continue;
} elseif ( $curChar == "\t" ) {
$counters['low']++;
continue;
} elseif ( ord( $curChar ) < 32 ) {
$counters['ctrl']++;
continue;
} elseif ( ord( $curChar ) >= 128 ) {
$counters['high']++;
continue;
}
$counters['low']++;
if ( $curChar == '<' ) {
// XML
$remainder = substr( $chunk, $offset + 1 );
if ( !strncasecmp( $remainder, '?XML', 4 ) ) {
$nextChar = substr( $chunk, $offset + 5, 1 );
if ( $nextChar == ':' || $nextChar == ' ' || $nextChar == "\t" ) {
$found['xml'] = true;
}
}
// Scriptlet (JSP)
if ( !strncasecmp( $remainder, 'SCRIPTLET', 9 ) ) {
$found['scriptlet'] = true;
break;
}
// HTML
foreach ( $htmlTags as $tag ) {
if ( !strncasecmp( $remainder, $tag, strlen( $tag ) ) ) {
$found['html'] = true;
}
}
// Skip broken check for additional tags (HR etc.)
// CHANNEL replaced by RSS, RDF and FEED in IE 7
if ( $version < 'ie07' ) {
if ( !strncasecmp( $remainder, 'CHANNEL', 7 ) ) {
$found['cdf'] = true;
}
} else {
// RSS
if ( !strncasecmp( $remainder, 'RSS', 3 ) ) {
$found['rss'] = true;
break; // return from SampleData
}
if ( !strncasecmp( $remainder, 'rdf:RDF', 7 ) ) {
$found['rdf-tag'] = true;
// no break
}
if ( !strncasecmp( $remainder, 'FEED', 4 ) ) {
$found['atom'] = true;
break;
}
}
continue;
}
// Skip broken check for -->
// RSS URL checks
// For some reason both URLs must appear before it is recognised
$remainder = substr( $chunk, $offset );
if ( !strncasecmp( $remainder, $rdfUrl, strlen( $rdfUrl ) ) ) {
$found['rdf-url'] = true;
if ( isset( $found['rdf-tag'] )
&& isset( $found['rdf-purl'] ) // [sic]
) {
break;
}
continue;
}
if ( !strncasecmp( $remainder, $rdfPurl, strlen( $rdfPurl ) ) ) {
if ( isset( $found['rdf-tag'] )
&& isset( $found['rdf-url'] ) // [sic]
) {
break;
}
continue;
}
// XBM checks
if ( !strncasecmp( $remainder, $xbmMagic1, strlen( $xbmMagic1 ) ) ) {
$found['xbm1'] = true;
continue;
}
if ( $curChar == '_' ) {
if ( isset( $found['xbm2'] ) ) {
if ( !strncasecmp( $remainder, $xbmMagic3, strlen( $xbmMagic3 ) ) ) {
$found['xbm'] = true;
break;
}
} elseif ( isset( $found['xbm1'] ) ) {
if ( !strncasecmp( $remainder, $xbmMagic2, strlen( $xbmMagic2 ) ) ) {
$found['xbm2'] = true;
}
}
}
// BinHex
if ( !strncmp( $remainder, $binhexMagic, strlen( $binhexMagic ) ) ) {
$found['binhex'] = true;
}
}
return [ 'found' => $found, 'counters' => $counters ];
}
/**
* @param string $version
* @param string|null $type
* @return int|string
*/
protected function getDataFormat( $version, $type ) {
$types = $this->typeTable[$version];
if ( $type == '(null)' || strval( $type ) === '' ) {
return 'ambiguous';
}
foreach ( $types as $format => $list ) {
if ( in_array( $type, $list ) ) {
return $format;
}
}
return 'unknown';
}
}
Zerion Mini Shell 1.0