Current File : /www/varak.net/wiki.varak.net/includes/MimeMagic.php
<?php
/**
* Module defining helper functions for detecting and dealing with MIME types.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
*/
/**
* Defines a set of well known MIME types
* This is used as a fallback to mime.types files.
* An extensive list of well known MIME types is provided by
* the file mime.types in the includes directory.
*
* This list concatenated with mime.types is used to create a MIME <-> ext
* map. Each line contains a MIME type followed by a space separated list of
* extensions. If multiple extensions for a single MIME type exist or if
* multiple MIME types exist for a single extension then in most cases
* MediaWiki assumes that the first extension following the MIME type is the
* canonical extension, and the first time a MIME type appears for a certain
* extension is considered the canonical MIME type.
*
* (Note that appending $wgMimeTypeFile to the end of MM_WELL_KNOWN_MIME_TYPES
* sucks because you can't redefine canonical types. This could be fixed by
* appending MM_WELL_KNOWN_MIME_TYPES behind $wgMimeTypeFile, but who knows
* what will break? In practice this probably isn't a problem anyway -- Bryan)
*/
define( 'MM_WELL_KNOWN_MIME_TYPES', <<<END_STRING
application/ogg ogx ogg ogm ogv oga spx
application/pdf pdf
application/vnd.oasis.opendocument.chart odc
application/vnd.oasis.opendocument.chart-template otc
application/vnd.oasis.opendocument.database odb
application/vnd.oasis.opendocument.formula odf
application/vnd.oasis.opendocument.formula-template otf
application/vnd.oasis.opendocument.graphics odg
application/vnd.oasis.opendocument.graphics-template otg
application/vnd.oasis.opendocument.image odi
application/vnd.oasis.opendocument.image-template oti
application/vnd.oasis.opendocument.presentation odp
application/vnd.oasis.opendocument.presentation-template otp
application/vnd.oasis.opendocument.spreadsheet ods
application/vnd.oasis.opendocument.spreadsheet-template ots
application/vnd.oasis.opendocument.text odt
application/vnd.oasis.opendocument.text-master otm
application/vnd.oasis.opendocument.text-template ott
application/vnd.oasis.opendocument.text-web oth
application/javascript js
application/x-shockwave-flash swf
audio/midi mid midi kar
audio/mpeg mpga mpa mp2 mp3
audio/x-aiff aif aiff aifc
audio/x-wav wav
audio/ogg oga spx ogg
image/x-bmp bmp
image/gif gif
image/jpeg jpeg jpg jpe
image/png png
image/svg+xml svg
image/svg svg
image/tiff tiff tif
image/vnd.djvu djvu
image/x.djvu djvu
image/x-djvu djvu
image/x-portable-pixmap ppm
image/x-xcf xcf
text/plain txt
text/html html htm
video/ogg ogv ogm ogg
video/mpeg mpg mpeg
END_STRING
);
/**
* Defines a set of well known MIME info entries
* This is used as a fallback to mime.info files.
* An extensive list of well known MIME types is provided by
* the file mime.info in the includes directory.
*/
define( 'MM_WELL_KNOWN_MIME_INFO', <<<END_STRING
application/pdf [OFFICE]
application/vnd.oasis.opendocument.chart [OFFICE]
application/vnd.oasis.opendocument.chart-template [OFFICE]
application/vnd.oasis.opendocument.database [OFFICE]
application/vnd.oasis.opendocument.formula [OFFICE]
application/vnd.oasis.opendocument.formula-template [OFFICE]
application/vnd.oasis.opendocument.graphics [OFFICE]
application/vnd.oasis.opendocument.graphics-template [OFFICE]
application/vnd.oasis.opendocument.image [OFFICE]
application/vnd.oasis.opendocument.image-template [OFFICE]
application/vnd.oasis.opendocument.presentation [OFFICE]
application/vnd.oasis.opendocument.presentation-template [OFFICE]
application/vnd.oasis.opendocument.spreadsheet [OFFICE]
application/vnd.oasis.opendocument.spreadsheet-template [OFFICE]
application/vnd.oasis.opendocument.text [OFFICE]
application/vnd.oasis.opendocument.text-template [OFFICE]
application/vnd.oasis.opendocument.text-master [OFFICE]
application/vnd.oasis.opendocument.text-web [OFFICE]
application/javascript text/javascript application/x-javascript [EXECUTABLE]
application/x-shockwave-flash [MULTIMEDIA]
audio/midi [AUDIO]
audio/x-aiff [AUDIO]
audio/x-wav [AUDIO]
audio/mp3 audio/mpeg [AUDIO]
application/ogg audio/ogg video/ogg [MULTIMEDIA]
image/x-bmp image/x-ms-bmp image/bmp [BITMAP]
image/gif [BITMAP]
image/jpeg [BITMAP]
image/png [BITMAP]
image/svg+xml [DRAWING]
image/tiff [BITMAP]
image/vnd.djvu [BITMAP]
image/x-xcf [BITMAP]
image/x-portable-pixmap [BITMAP]
text/plain [TEXT]
text/html [TEXT]
video/ogg [VIDEO]
video/mpeg [VIDEO]
unknown/unknown application/octet-stream application/x-empty [UNKNOWN]
END_STRING
);
/**
* Implements functions related to MIME types such as detection and mapping to
* file extension.
*
* Instances of this class are stateless, there only needs to be one global instance
* of MimeMagic. Please use MimeMagic::singleton() to get that instance.
*/
class MimeMagic {
/**
* @var array Mapping of media types to arrays of MIME types.
* This is used by findMediaType and getMediaType, respectively
*/
protected $mMediaTypes = null;
/** @var array Map of MIME type aliases
*/
protected $mMimeTypeAliases = null;
/** @var array Map of MIME types to file extensions (as a space separated list)
*/
protected $mMimeToExt = null;
/** @var array Map of file extensions types to MIME types (as a space separated list)
*/
public $mExtToMime = null;
/** @var IEContentAnalyzer
*/
protected $mIEAnalyzer;
/** @var string Extra MIME types, set for example by media handling extensions
*/
private $mExtraTypes = '';
/** @var string Extra MIME info, set for example by media handling extensions
*/
private $mExtraInfo = '';
/** @var Config */
private $mConfig;
/** @var MimeMagic The singleton instance
*/
private static $instance = null;
/** Initializes the MimeMagic object. This is called by MimeMagic::singleton().
*
* This constructor parses the mime.types and mime.info files and build internal mappings.
*
* @todo Make this constructor private once everything uses the singleton instance
* @param Config $config
*/
function __construct( Config $config = null ) {
if ( !$config ) {
wfDebug( __METHOD__ . ' called with no Config instance passed to it' );
$config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
}
$this->mConfig = $config;
/**
* --- load mime.types ---
*/
global $IP;
# Allow media handling extensions adding MIME-types and MIME-info
Hooks::run( 'MimeMagicInit', [ $this ] );
$types = MM_WELL_KNOWN_MIME_TYPES;
$mimeTypeFile = $this->mConfig->get( 'MimeTypeFile' );
if ( $mimeTypeFile == 'includes/mime.types' ) {
$mimeTypeFile = "$IP/$mimeTypeFile";
}
if ( $mimeTypeFile ) {
if ( is_file( $mimeTypeFile ) && is_readable( $mimeTypeFile ) ) {
wfDebug( __METHOD__ . ": loading mime types from $mimeTypeFile\n" );
$types .= "\n";
$types .= file_get_contents( $mimeTypeFile );
} else {
wfDebug( __METHOD__ . ": can't load mime types from $mimeTypeFile\n" );
}
} else {
wfDebug( __METHOD__ . ": no mime types file defined, using built-ins only.\n" );
}
$types .= "\n" . $this->mExtraTypes;
$types = str_replace( [ "\r\n", "\n\r", "\n\n", "\r\r", "\r" ], "\n", $types );
$types = str_replace( "\t", " ", $types );
$this->mMimeToExt = [];
$this->mExtToMime = [];
$lines = explode( "\n", $types );
foreach ( $lines as $s ) {
$s = trim( $s );
if ( empty( $s ) ) {
continue;
}
if ( strpos( $s, '#' ) === 0 ) {
continue;
}
$s = strtolower( $s );
$i = strpos( $s, ' ' );
if ( $i === false ) {
continue;
}
$mime = substr( $s, 0, $i );
$ext = trim( substr( $s, $i + 1 ) );
if ( empty( $ext ) ) {
continue;
}
if ( !empty( $this->mMimeToExt[$mime] ) ) {
$this->mMimeToExt[$mime] .= ' ' . $ext;
} else {
$this->mMimeToExt[$mime] = $ext;
}
$extensions = explode( ' ', $ext );
foreach ( $extensions as $e ) {
$e = trim( $e );
if ( empty( $e ) ) {
continue;
}
if ( !empty( $this->mExtToMime[$e] ) ) {
$this->mExtToMime[$e] .= ' ' . $mime;
} else {
$this->mExtToMime[$e] = $mime;
}
}
}
/**
* --- load mime.info ---
*/
$mimeInfoFile = $this->mConfig->get( 'MimeInfoFile' );
if ( $mimeInfoFile == 'includes/mime.info' ) {
$mimeInfoFile = "$IP/$mimeInfoFile";
}
$info = MM_WELL_KNOWN_MIME_INFO;
if ( $mimeInfoFile ) {
if ( is_file( $mimeInfoFile ) && is_readable( $mimeInfoFile ) ) {
wfDebug( __METHOD__ . ": loading mime info from $mimeInfoFile\n" );
$info .= "\n";
$info .= file_get_contents( $mimeInfoFile );
} else {
wfDebug( __METHOD__ . ": can't load mime info from $mimeInfoFile\n" );
}
} else {
wfDebug( __METHOD__ . ": no mime info file defined, using built-ins only.\n" );
}
$info .= "\n" . $this->mExtraInfo;
$info = str_replace( [ "\r\n", "\n\r", "\n\n", "\r\r", "\r" ], "\n", $info );
$info = str_replace( "\t", " ", $info );
$this->mMimeTypeAliases = [];
$this->mMediaTypes = [];
$lines = explode( "\n", $info );
foreach ( $lines as $s ) {
$s = trim( $s );
if ( empty( $s ) ) {
continue;
}
if ( strpos( $s, '#' ) === 0 ) {
continue;
}
$s = strtolower( $s );
$i = strpos( $s, ' ' );
if ( $i === false ) {
continue;
}
# print "processing MIME INFO line $s<br>";
$match = [];
if ( preg_match( '!\[\s*(\w+)\s*\]!', $s, $match ) ) {
$s = preg_replace( '!\[\s*(\w+)\s*\]!', '', $s );
$mtype = trim( strtoupper( $match[1] ) );
} else {
$mtype = MEDIATYPE_UNKNOWN;
}
$m = explode( ' ', $s );
if ( !isset( $this->mMediaTypes[$mtype] ) ) {
$this->mMediaTypes[$mtype] = [];
}
foreach ( $m as $mime ) {
$mime = trim( $mime );
if ( empty( $mime ) ) {
continue;
}
$this->mMediaTypes[$mtype][] = $mime;
}
if ( count( $m ) > 1 ) {
$main = $m[0];
$mCount = count( $m );
for ( $i = 1; $i < $mCount; $i += 1 ) {
$mime = $m[$i];
$this->mMimeTypeAliases[$mime] = $main;
}
}
}
}
/**
* Get an instance of this class
* @return MimeMagic
*/
public static function singleton() {
if ( self::$instance === null ) {
self::$instance = new MimeMagic(
ConfigFactory::getDefaultInstance()->makeConfig( 'main' )
);
}
return self::$instance;
}
/**
* Adds to the list mapping MIME to file extensions.
* As an extension author, you are encouraged to submit patches to
* MediaWiki's core to add new MIME types to mime.types.
* @param string $types
*/
public function addExtraTypes( $types ) {
$this->mExtraTypes .= "\n" . $types;
}
/**
* Adds to the list mapping MIME to media type.
* As an extension author, you are encouraged to submit patches to
* MediaWiki's core to add new MIME info to mime.info.
* @param string $info
*/
public function addExtraInfo( $info ) {
$this->mExtraInfo .= "\n" . $info;
}
/**
* Returns a list of file extensions for a given MIME type as a space
* separated string or null if the MIME type was unrecognized. Resolves
* MIME type aliases.
*
* @param string $mime
* @return string|null
*/
public function getExtensionsForType( $mime ) {
$mime = strtolower( $mime );
// Check the mime-to-ext map
if ( isset( $this->mMimeToExt[$mime] ) ) {
return $this->mMimeToExt[$mime];
}
// Resolve the MIME type to the canonical type
if ( isset( $this->mMimeTypeAliases[$mime] ) ) {
$mime = $this->mMimeTypeAliases[$mime];
if ( isset( $this->mMimeToExt[$mime] ) ) {
return $this->mMimeToExt[$mime];
}
}
return null;
}
/**
* Returns a list of MIME types for a given file extension as a space
* separated string or null if the extension was unrecognized.
*
* @param string $ext
* @return string|null
*/
public function getTypesForExtension( $ext ) {
$ext = strtolower( $ext );
$r = isset( $this->mExtToMime[$ext] ) ? $this->mExtToMime[$ext] : null;
return $r;
}
/**
* Returns a single MIME type for a given file extension or null if unknown.
* This is always the first type from the list returned by getTypesForExtension($ext).
*
* @param string $ext
* @return string|null
*/
public function guessTypesForExtension( $ext ) {
$m = $this->getTypesForExtension( $ext );
if ( is_null( $m ) ) {
return null;
}
// TODO: Check if this is needed; strtok( $m, ' ' ) should be sufficient
$m = trim( $m );
$m = preg_replace( '/\s.*$/', '', $m );
return $m;
}
/**
* Tests if the extension matches the given MIME type. Returns true if a
* match was found, null if the MIME type is unknown, and false if the
* MIME type is known but no matches where found.
*
* @param string $extension
* @param string $mime
* @return bool|null
*/
public function isMatchingExtension( $extension, $mime ) {
$ext = $this->getExtensionsForType( $mime );
if ( !$ext ) {
return null; // Unknown MIME type
}
$ext = explode( ' ', $ext );
$extension = strtolower( $extension );
return in_array( $extension, $ext );
}
/**
* Returns true if the MIME type is known to represent an image format
* supported by the PHP GD library.
*
* @param string $mime
*
* @return bool
*/
public function isPHPImageType( $mime ) {
// As defined by imagegetsize and image_type_to_mime
static $types = [
'image/gif', 'image/jpeg', 'image/png',
'image/x-bmp', 'image/xbm', 'image/tiff',
'image/jp2', 'image/jpeg2000', 'image/iff',
'image/xbm', 'image/x-xbitmap',
'image/vnd.wap.wbmp', 'image/vnd.xiff',
'image/x-photoshop',
'application/x-shockwave-flash',
];
return in_array( $mime, $types );
}
/**
* Returns true if the extension represents a type which can
* be reliably detected from its content. Use this to determine
* whether strict content checks should be applied to reject
* invalid uploads; if we can't identify the type we won't
* be able to say if it's invalid.
*
* @todo Be more accurate when using fancy MIME detector plugins;
* right now this is the bare minimum getimagesize() list.
* @param string $extension
* @return bool
*/
function isRecognizableExtension( $extension ) {
static $types = [
// Types recognized by getimagesize()
'gif', 'jpeg', 'jpg', 'png', 'swf', 'psd',
'bmp', 'tiff', 'tif', 'jpc', 'jp2',
'jpx', 'jb2', 'swc', 'iff', 'wbmp',
'xbm',
// Formats we recognize magic numbers for
'djvu', 'ogx', 'ogg', 'ogv', 'oga', 'spx',
'mid', 'pdf', 'wmf', 'xcf', 'webm', 'mkv', 'mka',
'webp',
// XML formats we sure hope we recognize reliably
'svg',
];
return in_array( strtolower( $extension ), $types );
}
/**
* Improves a MIME type using the file extension. Some file formats are very generic,
* so their MIME type is not very meaningful. A more useful MIME type can be derived
* by looking at the file extension. Typically, this method would be called on the
* result of guessMimeType().
*
* @param string $mime The MIME type, typically guessed from a file's content.
* @param string $ext The file extension, as taken from the file name
*
* @return string The MIME type
*/
public function improveTypeFromExtension( $mime, $ext ) {
if ( $mime === 'unknown/unknown' ) {
if ( $this->isRecognizableExtension( $ext ) ) {
wfDebug( __METHOD__ . ': refusing to guess mime type for .' .
"$ext file, we should have recognized it\n" );
} else {
// Not something we can detect, so simply
// trust the file extension
$mime = $this->guessTypesForExtension( $ext );
}
} elseif ( $mime === 'application/x-opc+zip' ) {
if ( $this->isMatchingExtension( $ext, $mime ) ) {
// A known file extension for an OPC file,
// find the proper MIME type for that file extension
$mime = $this->guessTypesForExtension( $ext );
} else {
wfDebug( __METHOD__ . ": refusing to guess better type for $mime file, " .
".$ext is not a known OPC extension.\n" );
$mime = 'application/zip';
}
} elseif ( $mime === 'text/plain' && $this->findMediaType( ".$ext" ) === MEDIATYPE_TEXT ) {
// Textual types are sometimes not recognized properly.
// If detected as text/plain, and has an extension which is textual
// improve to the extension's type. For example, csv and json are often
// misdetected as text/plain.
$mime = $this->guessTypesForExtension( $ext );
}
# Media handling extensions can improve the MIME detected
Hooks::run( 'MimeMagicImproveFromExtension', [ $this, $ext, &$mime ] );
if ( isset( $this->mMimeTypeAliases[$mime] ) ) {
$mime = $this->mMimeTypeAliases[$mime];
}
wfDebug( __METHOD__ . ": improved mime type for .$ext: $mime\n" );
return $mime;
}
/**
* MIME type detection. This uses detectMimeType to detect the MIME type
* of the file, but applies additional checks to determine some well known
* file formats that may be missed or misinterpreted by the default MIME
* detection (namely XML based formats like XHTML or SVG, as well as ZIP
* based formats like OPC/ODF files).
*
* @param string $file The file to check
* @param string|bool $ext The file extension, or true (default) to extract it from the filename.
* Set it to false to ignore the extension. DEPRECATED! Set to false, use
* improveTypeFromExtension($mime, $ext) later to improve MIME type.
*
* @return string The MIME type of $file
*/
public function guessMimeType( $file, $ext = true ) {
if ( $ext ) { // TODO: make $ext default to false. Or better, remove it.
wfDebug( __METHOD__ . ": WARNING: use of the \$ext parameter is deprecated. " .
"Use improveTypeFromExtension(\$mime, \$ext) instead.\n" );
}
$mime = $this->doGuessMimeType( $file, $ext );
if ( !$mime ) {
wfDebug( __METHOD__ . ": internal type detection failed for $file (.$ext)...\n" );
$mime = $this->detectMimeType( $file, $ext );
}
if ( isset( $this->mMimeTypeAliases[$mime] ) ) {
$mime = $this->mMimeTypeAliases[$mime];
}
wfDebug( __METHOD__ . ": guessed mime type of $file: $mime\n" );
return $mime;
}
/**
* Guess the MIME type from the file contents.
*
* @todo Remove $ext param
*
* @param string $file
* @param mixed $ext
* @return bool|string
* @throws MWException
*/
private function doGuessMimeType( $file, $ext ) {
// Read a chunk of the file
MediaWiki\suppressWarnings();
$f = fopen( $file, 'rb' );
MediaWiki\restoreWarnings();
if ( !$f ) {
return 'unknown/unknown';
}
$fsize = filesize( $file );
if ( $fsize === false ) {
return 'unknown/unknown';
}
$head = fread( $f, 1024 );
$tailLength = min( 65558, $fsize ); // 65558 = maximum size of a zip EOCDR
if ( fseek( $f, -1 * $tailLength, SEEK_END ) === -1 ) {
throw new MWException(
"Seeking $tailLength bytes from EOF failed in " . __METHOD__ );
}
$tail = $tailLength ? fread( $f, $tailLength ) : '';
fclose( $f );
wfDebug( __METHOD__ . ": analyzing head and tail of $file for magic numbers.\n" );
// Hardcode a few magic number checks...
$headers = [
// Multimedia...
'MThd' => 'audio/midi',
'OggS' => 'application/ogg',
// Image formats...
// Note that WMF may have a bare header, no magic number.
"\x01\x00\x09\x00" => 'application/x-msmetafile', // Possibly prone to false positives?
"\xd7\xcd\xc6\x9a" => 'application/x-msmetafile',
'%PDF' => 'application/pdf',
'gimp xcf' => 'image/x-xcf',
// Some forbidden fruit...
'MZ' => 'application/octet-stream', // DOS/Windows executable
"\xca\xfe\xba\xbe" => 'application/octet-stream', // Mach-O binary
"\x7fELF" => 'application/octet-stream', // ELF binary
];
foreach ( $headers as $magic => $candidate ) {
if ( strncmp( $head, $magic, strlen( $magic ) ) == 0 ) {
wfDebug( __METHOD__ . ": magic header in $file recognized as $candidate\n" );
return $candidate;
}
}
/* Look for WebM and Matroska files */
if ( strncmp( $head, pack( "C4", 0x1a, 0x45, 0xdf, 0xa3 ), 4 ) == 0 ) {
$doctype = strpos( $head, "\x42\x82" );
if ( $doctype ) {
// Next byte is datasize, then data (sizes larger than 1 byte are very stupid muxers)
$data = substr( $head, $doctype + 3, 8 );
if ( strncmp( $data, "matroska", 8 ) == 0 ) {
wfDebug( __METHOD__ . ": recognized file as video/x-matroska\n" );
return "video/x-matroska";
} elseif ( strncmp( $data, "webm", 4 ) == 0 ) {
wfDebug( __METHOD__ . ": recognized file as video/webm\n" );
return "video/webm";
}
}
wfDebug( __METHOD__ . ": unknown EBML file\n" );
return "unknown/unknown";
}
/* Look for WebP */
if ( strncmp( $head, "RIFF", 4 ) == 0 && strncmp( substr( $head, 8, 7 ), "WEBPVP8", 7 ) == 0 ) {
wfDebug( __METHOD__ . ": recognized file as image/webp\n" );
return "image/webp";
}
/**
* Look for PHP. Check for this before HTML/XML... Warning: this is a
* heuristic, and won't match a file with a lot of non-PHP before. It
* will also match text files which could be PHP. :)
*
* @todo FIXME: For this reason, the check is probably useless -- an attacker
* could almost certainly just pad the file with a lot of nonsense to
* circumvent the check in any case where it would be a security
* problem. On the other hand, it causes harmful false positives (bug
* 16583). The heuristic has been cut down to exclude three-character
* strings like "<? ", but should it be axed completely?
*/
if ( ( strpos( $head, '<?php' ) !== false ) ||
( strpos( $head, "<\x00?\x00p\x00h\x00p" ) !== false ) ||
( strpos( $head, "<\x00?\x00 " ) !== false ) ||
( strpos( $head, "<\x00?\x00\n" ) !== false ) ||
( strpos( $head, "<\x00?\x00\t" ) !== false ) ||
( strpos( $head, "<\x00?\x00=" ) !== false ) ) {
wfDebug( __METHOD__ . ": recognized $file as application/x-php\n" );
return 'application/x-php';
}
/**
* look for XML formats (XHTML and SVG)
*/
$xml = new XmlTypeCheck( $file );
if ( $xml->wellFormed ) {
$xmlMimeTypes = $this->mConfig->get( 'XMLMimeTypes' );
if ( isset( $xmlMimeTypes[$xml->getRootElement()] ) ) {
return $xmlMimeTypes[$xml->getRootElement()];
} else {
return 'application/xml';
}
}
/**
* look for shell scripts
*/
$script_type = null;
# detect by shebang
if ( substr( $head, 0, 2 ) == "#!" ) {
$script_type = "ASCII";
} elseif ( substr( $head, 0, 5 ) == "\xef\xbb\xbf#!" ) {
$script_type = "UTF-8";
} elseif ( substr( $head, 0, 7 ) == "\xfe\xff\x00#\x00!" ) {
$script_type = "UTF-16BE";
} elseif ( substr( $head, 0, 7 ) == "\xff\xfe#\x00!" ) {
$script_type = "UTF-16LE";
}
if ( $script_type ) {
if ( $script_type !== "UTF-8" && $script_type !== "ASCII" ) {
// Quick and dirty fold down to ASCII!
$pack = [ 'UTF-16BE' => 'n*', 'UTF-16LE' => 'v*' ];
$chars = unpack( $pack[$script_type], substr( $head, 2 ) );
$head = '';
foreach ( $chars as $codepoint ) {
if ( $codepoint < 128 ) {
$head .= chr( $codepoint );
} else {
$head .= '?';
}
}
}
$match = [];
if ( preg_match( '%/?([^\s]+/)(\w+)%', $head, $match ) ) {
$mime = "application/x-{$match[2]}";
wfDebug( __METHOD__ . ": shell script recognized as $mime\n" );
return $mime;
}
}
// Check for ZIP variants (before getimagesize)
if ( strpos( $tail, "PK\x05\x06" ) !== false ) {
wfDebug( __METHOD__ . ": ZIP header present in $file\n" );
return $this->detectZipType( $head, $tail, $ext );
}
MediaWiki\suppressWarnings();
$gis = getimagesize( $file );
MediaWiki\restoreWarnings();
if ( $gis && isset( $gis['mime'] ) ) {
$mime = $gis['mime'];
wfDebug( __METHOD__ . ": getimagesize detected $file as $mime\n" );
return $mime;
}
// Also test DjVu
$deja = new DjVuImage( $file );
if ( $deja->isValid() ) {
wfDebug( __METHOD__ . ": detected $file as image/vnd.djvu\n" );
return 'image/vnd.djvu';
}
# Media handling extensions can guess the MIME by content
# It's intentionally here so that if core is wrong about a type (false positive),
# people will hopefully nag and submit patches :)
$mime = false;
# Some strings by reference for performance - assuming well-behaved hooks
Hooks::run(
'MimeMagicGuessFromContent',
[ $this, &$head, &$tail, $file, &$mime ]
);
return $mime;
}
/**
* Detect application-specific file type of a given ZIP file from its
* header data. Currently works for OpenDocument and OpenXML types...
* If can't tell, returns 'application/zip'.
*
* @param string $header Some reasonably-sized chunk of file header
* @param string|null $tail The tail of the file
* @param string|bool $ext The file extension, or true to extract it from the filename.
* Set it to false (default) to ignore the extension. DEPRECATED! Set to false,
* use improveTypeFromExtension($mime, $ext) later to improve MIME type.
*
* @return string
*/
function detectZipType( $header, $tail = null, $ext = false ) {
if ( $ext ) { # TODO: remove $ext param
wfDebug( __METHOD__ . ": WARNING: use of the \$ext parameter is deprecated. " .
"Use improveTypeFromExtension(\$mime, \$ext) instead.\n" );
}
$mime = 'application/zip';
$opendocTypes = [
'chart-template',
'chart',
'formula-template',
'formula',
'graphics-template',
'graphics',
'image-template',
'image',
'presentation-template',
'presentation',
'spreadsheet-template',
'spreadsheet',
'text-template',
'text-master',
'text-web',
'text' ];
// http://lists.oasis-open.org/archives/office/200505/msg00006.html
$types = '(?:' . implode( '|', $opendocTypes ) . ')';
$opendocRegex = "/^mimetype(application\/vnd\.oasis\.opendocument\.$types)/";
$openxmlRegex = "/^\[Content_Types\].xml/";
if ( preg_match( $opendocRegex, substr( $header, 30 ), $matches ) ) {
$mime = $matches[1];
wfDebug( __METHOD__ . ": detected $mime from ZIP archive\n" );
} elseif ( preg_match( $openxmlRegex, substr( $header, 30 ) ) ) {
$mime = "application/x-opc+zip";
# TODO: remove the block below, as soon as improveTypeFromExtension is used everywhere
if ( $ext !== true && $ext !== false ) {
// These MIME's are stored in the database, where we don't really want
// x-opc+zip, because we use it only for internal purposes
if ( $this->isMatchingExtension( $ext, $mime ) ) {
/* A known file extension for an OPC file,
* find the proper mime type for that file extension
*/
$mime = $this->guessTypesForExtension( $ext );
} else {
$mime = "application/zip";
}
}
wfDebug( __METHOD__ . ": detected an Open Packaging Conventions archive: $mime\n" );
} elseif ( substr( $header, 0, 8 ) == "\xd0\xcf\x11\xe0\xa1\xb1\x1a\xe1" &&
( $headerpos = strpos( $tail, "PK\x03\x04" ) ) !== false &&
preg_match( $openxmlRegex, substr( $tail, $headerpos + 30 ) ) ) {
if ( substr( $header, 512, 4 ) == "\xEC\xA5\xC1\x00" ) {
$mime = "application/msword";
}
switch ( substr( $header, 512, 6 ) ) {
case "\xEC\xA5\xC1\x00\x0E\x00":
case "\xEC\xA5\xC1\x00\x1C\x00":
case "\xEC\xA5\xC1\x00\x43\x00":
$mime = "application/vnd.ms-powerpoint";
break;
case "\xFD\xFF\xFF\xFF\x10\x00":
case "\xFD\xFF\xFF\xFF\x1F\x00":
case "\xFD\xFF\xFF\xFF\x22\x00":
case "\xFD\xFF\xFF\xFF\x23\x00":
case "\xFD\xFF\xFF\xFF\x28\x00":
case "\xFD\xFF\xFF\xFF\x29\x00":
case "\xFD\xFF\xFF\xFF\x10\x02":
case "\xFD\xFF\xFF\xFF\x1F\x02":
case "\xFD\xFF\xFF\xFF\x22\x02":
case "\xFD\xFF\xFF\xFF\x23\x02":
case "\xFD\xFF\xFF\xFF\x28\x02":
case "\xFD\xFF\xFF\xFF\x29\x02":
$mime = "application/vnd.msexcel";
break;
}
wfDebug( __METHOD__ . ": detected a MS Office document with OPC trailer\n" );
} else {
wfDebug( __METHOD__ . ": unable to identify type of ZIP archive\n" );
}
return $mime;
}
/**
* Internal MIME type detection. Detection is done using an external
* program, if $wgMimeDetectorCommand is set. Otherwise, the fileinfo
* extension is tried if it is available. If detection fails and $ext
* is not false, the MIME type is guessed from the file extension,
* using guessTypesForExtension.
*
* If the MIME type is still unknown, getimagesize is used to detect the
* MIME type if the file is an image. If no MIME type can be determined,
* this function returns 'unknown/unknown'.
*
* @param string $file The file to check
* @param string|bool $ext The file extension, or true (default) to extract it from the filename.
* Set it to false to ignore the extension. DEPRECATED! Set to false, use
* improveTypeFromExtension($mime, $ext) later to improve MIME type.
*
* @return string The MIME type of $file
*/
private function detectMimeType( $file, $ext = true ) {
/** @todo Make $ext default to false. Or better, remove it. */
if ( $ext ) {
wfDebug( __METHOD__ . ": WARNING: use of the \$ext parameter is deprecated. "
. "Use improveTypeFromExtension(\$mime, \$ext) instead.\n" );
}
$mimeDetectorCommand = $this->mConfig->get( 'MimeDetectorCommand' );
$m = null;
if ( $mimeDetectorCommand ) {
$args = wfEscapeShellArg( $file );
$m = wfShellExec( "$mimeDetectorCommand $args" );
} elseif ( function_exists( "finfo_open" ) && function_exists( "finfo_file" ) ) {
$mime_magic_resource = finfo_open( FILEINFO_MIME );
if ( $mime_magic_resource ) {
$m = finfo_file( $mime_magic_resource, $file );
finfo_close( $mime_magic_resource );
} else {
wfDebug( __METHOD__ . ": finfo_open failed on " . FILEINFO_MIME . "!\n" );
}
} else {
wfDebug( __METHOD__ . ": no magic mime detector found!\n" );
}
if ( $m ) {
# normalize
$m = preg_replace( '![;, ].*$!', '', $m ); # strip charset, etc
$m = trim( $m );
$m = strtolower( $m );
if ( strpos( $m, 'unknown' ) !== false ) {
$m = null;
} else {
wfDebug( __METHOD__ . ": magic mime type of $file: $m\n" );
return $m;
}
}
// If desired, look at extension as a fallback.
if ( $ext === true ) {
$i = strrpos( $file, '.' );
$ext = strtolower( $i ? substr( $file, $i + 1 ) : '' );
}
if ( $ext ) {
if ( $this->isRecognizableExtension( $ext ) ) {
wfDebug( __METHOD__ . ": refusing to guess mime type for .$ext file, "
. "we should have recognized it\n" );
} else {
$m = $this->guessTypesForExtension( $ext );
if ( $m ) {
wfDebug( __METHOD__ . ": extension mime type of $file: $m\n" );
return $m;
}
}
}
// Unknown type
wfDebug( __METHOD__ . ": failed to guess mime type for $file!\n" );
return 'unknown/unknown';
}
/**
* Determine the media type code for a file, using its MIME type, name and
* possibly its contents.
*
* This function relies on the findMediaType(), mapping extensions and MIME
* types to media types.
*
* @todo analyse file if need be
* @todo look at multiple extension, separately and together.
*
* @param string $path Full path to the image file, in case we have to look at the contents
* (if null, only the MIME type is used to determine the media type code).
* @param string $mime MIME type. If null it will be guessed using guessMimeType.
*
* @return string A value to be used with the MEDIATYPE_xxx constants.
*/
function getMediaType( $path = null, $mime = null ) {
if ( !$mime && !$path ) {
return MEDIATYPE_UNKNOWN;
}
// If MIME type is unknown, guess it
if ( !$mime ) {
$mime = $this->guessMimeType( $path, false );
}
// Special code for ogg - detect if it's video (theora),
// else label it as sound.
if ( $mime == 'application/ogg' && file_exists( $path ) ) {
// Read a chunk of the file
$f = fopen( $path, "rt" );
if ( !$f ) {
return MEDIATYPE_UNKNOWN;
}
$head = fread( $f, 256 );
fclose( $f );
$head = str_replace( 'ffmpeg2theora', '', strtolower( $head ) );
// This is an UGLY HACK, file should be parsed correctly
if ( strpos( $head, 'theora' ) !== false ) {
return MEDIATYPE_VIDEO;
} elseif ( strpos( $head, 'vorbis' ) !== false ) {
return MEDIATYPE_AUDIO;
} elseif ( strpos( $head, 'flac' ) !== false ) {
return MEDIATYPE_AUDIO;
} elseif ( strpos( $head, 'speex' ) !== false ) {
return MEDIATYPE_AUDIO;
} else {
return MEDIATYPE_MULTIMEDIA;
}
}
$type = null;
// Check for entry for full MIME type
if ( $mime ) {
$type = $this->findMediaType( $mime );
if ( $type !== MEDIATYPE_UNKNOWN ) {
return $type;
}
}
// Check for entry for file extension
if ( $path ) {
$i = strrpos( $path, '.' );
$e = strtolower( $i ? substr( $path, $i + 1 ) : '' );
// TODO: look at multi-extension if this fails, parse from full path
$type = $this->findMediaType( '.' . $e );
if ( $type !== MEDIATYPE_UNKNOWN ) {
return $type;
}
}
// Check major MIME type
if ( $mime ) {
$i = strpos( $mime, '/' );
if ( $i !== false ) {
$major = substr( $mime, 0, $i );
$type = $this->findMediaType( $major );
if ( $type !== MEDIATYPE_UNKNOWN ) {
return $type;
}
}
}
if ( !$type ) {
$type = MEDIATYPE_UNKNOWN;
}
return $type;
}
/**
* Returns a media code matching the given MIME type or file extension.
* File extensions are represented by a string starting with a dot (.) to
* distinguish them from MIME types.
*
* This function relies on the mapping defined by $this->mMediaTypes
* @access private
* @param string $extMime
* @return int|string
*/
function findMediaType( $extMime ) {
if ( strpos( $extMime, '.' ) === 0 ) {
// If it's an extension, look up the MIME types
$m = $this->getTypesForExtension( substr( $extMime, 1 ) );
if ( !$m ) {
return MEDIATYPE_UNKNOWN;
}
$m = explode( ' ', $m );
} else {
// Normalize MIME type
if ( isset( $this->mMimeTypeAliases[$extMime] ) ) {
$extMime = $this->mMimeTypeAliases[$extMime];
}
$m = [ $extMime ];
}
foreach ( $m as $mime ) {
foreach ( $this->mMediaTypes as $type => $codes ) {
if ( in_array( $mime, $codes, true ) ) {
return $type;
}
}
}
return MEDIATYPE_UNKNOWN;
}
/**
* Get the MIME types that various versions of Internet Explorer would
* detect from a chunk of the content.
*
* @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
*/
public function getIEMimeTypes( $fileName, $chunk, $proposed ) {
$ca = $this->getIEContentAnalyzer();
return $ca->getRealMimesFromData( $fileName, $chunk, $proposed );
}
/**
* Get a cached instance of IEContentAnalyzer
*
* @return IEContentAnalyzer
*/
protected function getIEContentAnalyzer() {
if ( is_null( $this->mIEAnalyzer ) ) {
$this->mIEAnalyzer = new IEContentAnalyzer;
}
return $this->mIEAnalyzer;
}
}
Mini Shell