X-Git-Url: https://git.heureux-cyclage.org/?a=blobdiff_plain;f=includes%2FMimeMagic.php;h=cde30bc009978117c0550ec0d7558a7737f1de69;hb=92ec8a2bec1c34474e5450eec34203c19f253908;hp=77a306214a679070911008cf697a1fb741b60efd;hpb=d3ddd6efdbfefa8065a2abcdbcb019b3effd209b;p=lhc%2Fweb%2Fwiklou.git diff --git a/includes/MimeMagic.php b/includes/MimeMagic.php index 77a306214a..cde30bc009 100644 --- a/includes/MimeMagic.php +++ b/includes/MimeMagic.php @@ -1,23 +1,42 @@ getTypesForExtension( $ext ); - if ( is_null( $m ) ) return NULL; + if ( is_null( $m ) ) return null; $m = trim( $m ); $m = preg_replace( '/\s.*$/', '', $m ); @@ -309,7 +349,7 @@ class MimeMagic { $ext = $this->getExtensionsForType( $mime ); if ( !$ext ) { - return NULL; //unknown + return null; //unknown } $ext = explode( ' ', $ext ); @@ -358,28 +398,84 @@ class MimeMagic { 'bmp', 'tiff', 'tif', 'jpc', 'jp2', 'jpx', 'jb2', 'swc', 'iff', 'wbmp', 'xbm', - + // Formats we recognize magic numbers for - 'djvu', 'ogg', 'mid', 'pdf', 'wmf', 'xcf', - + 'djvu', 'ogx', 'ogg', 'ogv', 'oga', 'spx', + 'mid', 'pdf', 'wmf', 'xcf', 'webm', 'mkv', 'mka', + // 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(). + * + * Currently, this method does the following: + * + * If $mime is "unknown/unknown" and isRecognizableExtension( $ext ) returns false, + * return the result of guessTypesForExtension($ext). + * + * If $mime is "application/x-opc+zip" and isMatchingExtension( $ext, $mime ) + * gives true, return the result of guessTypesForExtension($ext). + * + * @param $mime String: the mime type, typically guessed from a file's content. + * @param $ext String: the file extension, as taken from the file name + * + * @return string the mime type + */ + 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 ); + } + } + else if ( $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"; + } + } + + 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 misinterpreter by the default mime detection (namely xml based formats like XHTML or SVG). + * or misinterpreter 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 mixed $ext The file extension, or true to extract it from the filename. - * Set it to false to ignore the extension. + * @param $file String: the file to check + * @param $ext Mixed: the file extension, or true (default) to extract it from the filename. + * Set it to false to ignore the extension. DEPRECATED! Set to false, use + * improveTypeFromExtension($mime, $ext) later to improve mime type. * * @return string the mime type of $file */ 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 ) { @@ -391,38 +487,42 @@ class MimeMagic { $mime = $this->mMimeTypeAliases[$mime]; } - wfDebug(__METHOD__.": final mime type of $file: $mime\n"); + wfDebug(__METHOD__.": guessed mime type of $file: $mime\n"); return $mime; } - - function doGuessMimeType( $file, $ext = true ) { + + private function doGuessMimeType( $file, $ext ) { # TODO: remove $ext param // Read a chunk of the file wfSuppressWarnings(); $f = fopen( $file, "rt" ); wfRestoreWarnings(); if( !$f ) return "unknown/unknown"; $head = fread( $f, 1024 ); + fseek( $f, -65558, SEEK_END ); + $tail = fread( $f, 65558 ); // 65558 = maximum size of a zip EOCDR fclose( $f ); + wfDebug( __METHOD__ . ": analyzing head and tail of $file for magic numbers.\n" ); + // Hardcode a few magic number checks... $headers = array( // 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', + '%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" ); @@ -430,17 +530,37 @@ class MimeMagic { } } + /* 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"; + } else if ( 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 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. :) + * 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. :) + * + * 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 " 126 ) { - printf( "\\x%02x", $c ); - } else { - print $head{$i}; - } - } - echo "\n"; - */ - } - - if( $xml_type == 'UTF-16BE' || $xml_type == 'UTF-16LE' ) { - // Quick and dirty fold down to ASCII! - $pack = array( 'UTF-16BE' => 'n*', 'UTF-16LE' => 'v*' ); - $chars = unpack( $pack[$xml_type], substr( $head, 2 ) ); - $head = ''; - foreach( $chars as $codepoint ) { - if( $codepoint < 128 ) { - $head .= chr( $codepoint ); - } else { - $head .= '?'; - } - } - } - - $match = array(); - $doctype = ""; - $tag = ""; - - if ( preg_match( '%%siD', - $head, $match ) ) { - $doctype = $match[1]; - } - - if( $xml_type || $doctype ) { - if ( preg_match( '%<(\w+)\b%si', $head, $match ) ) { - $tag = $match[1]; - } - - #print "
ANALYSING $file: doctype= $doctype; tag= $tag
"; - - if ( strpos( $doctype, "-//W3C//DTD SVG" ) === 0 ) { - return "image/svg+xml"; - } elseif ( $tag === "svg" ) { - return "image/svg+xml"; - } elseif ( strpos( $doctype, "-//W3C//DTD XHTML" ) === 0 ) { - return "text/html"; - } elseif ( $tag === "html" ) { - return "text/html"; + $xml = new XmlTypeCheck( $file ); + if( $xml->wellFormed ) { + global $wgXMLMimeTypes; + if( isset( $wgXMLMimeTypes[$xml->getRootElement()] ) ) { + return $wgXMLMimeTypes[$xml->getRootElement()]; } else { - /// Fixme -- this would be the place to allow additional XML type checks - return "application/xml"; + return 'application/xml'; } } /* * look for shell scripts */ - $script_type = NULL; + $script_type = null; # detect by shebang if ( substr( $head, 0, 2) == "#!" ) { @@ -541,7 +603,17 @@ class MimeMagic { if ( $script_type ) { if ( $script_type !== "UTF-8" && $script_type !== "ASCII") { - $head = iconv( $script_type, "ASCII//IGNORE", $head); + // Quick and dirty fold down to ASCII! + $pack = array( '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 = array(); @@ -552,17 +624,21 @@ class MimeMagic { 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 ); + } + wfSuppressWarnings(); $gis = getimagesize( $file ); wfRestoreWarnings(); - + if( $gis && isset( $gis['mime'] ) ) { $mime = $gis['mime']; wfDebug( __METHOD__.": getimagesize detected $file as $mime\n" ); return $mime; - } else { - return false; } // Also test DjVu @@ -571,27 +647,133 @@ class MimeMagic { wfDebug( __METHOD__.": detected $file as image/vnd.djvu\n" ); return 'image/vnd.djvu'; } + + return false; + } + + /** + * 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 $header String: some reasonably-sized chunk of file header + * @param $tail String: the tail of the file + * @param $ext Mixed: the file extension, or true to extract it from the filename. + * Set it to false (default) to ignore the extension. DEPRECATED! Set to false, + * use improveTypeFromExtension($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 = array( + '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 ) { + /** This is the mode used by getPropsFromPath + * 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" ); + } else if( 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, please use guessMimeType() for application code instead. * Detection is done using an external program, if $wgMimeDetectorCommand is set. * Otherwise, the fileinfo extension and mime_content_type are tried (in this order), if they are available. - * If the dections fails and $ext is not false, the mime type is guessed from the file extension, using + * If the dections 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 mixed $ext The file extension, or true to extract it from the filename. - * Set it to false to ignore the extension. + * @param $file String: the file to check + * @param $ext Mixed: the file extension, or true (default) to extract it from the filename. + * Set it to false to ignore the extension. DEPRECATED! Set to false, use + * improveTypeFromExtension($mime, $ext) later to improve mime type. * * @return string the mime type of $file * @access private */ - function detectMimeType( $file, $ext = true ) { + private function detectMimeType( $file, $ext = true ) { global $wgMimeDetectorCommand; - $m = NULL; + 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" ); + } + + $m = null; if ( $wgMimeDetectorCommand ) { $fn = wfEscapeShellArg( $file ); $m = `$wgMimeDetectorCommand $fn`; @@ -638,7 +820,7 @@ class MimeMagic { $m = strtolower( $m ); if ( strpos( $m, 'unknown' ) !== false ) { - $m = NULL; + $m = null; } else { wfDebug( __METHOD__.": magic mime type of $file: $m\n" ); return $m; @@ -677,13 +859,13 @@ class MimeMagic { * @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 + * @param $path String: 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. + * @param $mime String: mime type. If null it will be guessed using guessMimeType. * * @return (int?string?) a value to be used with the MEDIATYPE_xxx constants. */ - function getMediaType( $path = NULL, $mime = NULL ) { + function getMediaType( $path = null, $mime = null ) { if( !$mime && !$path ) return MEDIATYPE_UNKNOWN; # If mime type is unknown, guess it @@ -716,7 +898,7 @@ class MimeMagic { } # Check for entry for file extension - $e = NULL; + $e = null; if ( $path ) { $i = strrpos( $path, '.' ); $e = strtolower( $i ? substr( $path, $i + 1 ) : '' ); @@ -755,7 +937,7 @@ class MimeMagic { if ( !$m ) return MEDIATYPE_UNKNOWN; $m = explode( ' ', $m ); - } else { + } else { # Normalize mime type if ( isset( $this->mMimeTypeAliases[$extMime] ) ) { $extMime = $this->mMimeTypeAliases[$extMime]; @@ -774,6 +956,27 @@ class MimeMagic { return MEDIATYPE_UNKNOWN; } -} + /** + * Get the MIME types that various versions of Internet Explorer would + * detect from a chunk of the content. + * + * @param $fileName String: the file name (unused at present) + * @param $chunk String: the first 256 bytes of the file + * @param $proposed String: the MIME type proposed by the server + */ + public function getIEMimeTypes( $fileName, $chunk, $proposed ) { + $ca = $this->getIEContentAnalyzer(); + return $ca->getRealMimesFromData( $fileName, $chunk, $proposed ); + } + /** + * Get a cached instance of IEContentAnalyzer + */ + protected function getIEContentAnalyzer() { + if ( is_null( $this->mIEAnalyzer ) ) { + $this->mIEAnalyzer = new IEContentAnalyzer; + } + return $this->mIEAnalyzer; + } +}