"use strict"; var readerFor = require("./reader/readerFor"); var utils = require("./utils"); var CompressedObject = require("./compressedObject"); var crc32fn = require("./crc32"); var utf8 = require("./utf8"); var compressions = require("./compressions"); var support = require("./support"); var MADE_BY_DOS = 0x00; var MADE_BY_UNIX = 0x03; /** * Find a compression registered in JSZip. * @param {string} compressionMethod the method magic to find. * @return {Object|null} the JSZip compression object, null if none found. */ var findCompression = function(compressionMethod) { for (var method in compressions) { if (!Object.prototype.hasOwnProperty.call(compressions, method)) { continue; } if (compressions[method].magic === compressionMethod) { return compressions[method]; } } return null; }; // class ZipEntry {{{ /** * An entry in the zip file. * @constructor * @param {Object} options Options of the current file. * @param {Object} loadOptions Options for loading the stream. */ function ZipEntry(options, loadOptions) { this.options = options; this.loadOptions = loadOptions; } ZipEntry.prototype = { /** * say if the file is encrypted. * @return {boolean} true if the file is encrypted, false otherwise. */ isEncrypted: function() { // bit 1 is set return (this.bitFlag & 0x0001) === 0x0001; }, /** * say if the file has utf-8 filename/comment. * @return {boolean} true if the filename/comment is in utf-8, false otherwise. */ useUTF8: function() { // bit 11 is set return (this.bitFlag & 0x0800) === 0x0800; }, /** * Read the local part of a zip file and add the info in this object. * @param {DataReader} reader the reader to use. */ readLocalPart: function(reader) { var compression, localExtraFieldsLength; // we already know everything from the central dir ! // If the central dir data are false, we are doomed. // On the bright side, the local part is scary : zip64, data descriptors, both, etc. // The less data we get here, the more reliable this should be. // Let's skip the whole header and dash to the data ! reader.skip(22); // in some zip created on windows, the filename stored in the central dir contains \ instead of /. // Strangely, the filename here is OK. // I would love to treat these zip files as corrupted (see http://www.info-zip.org/FAQ.html#backslashes // or APPNOTE#4.4.17.1, "All slashes MUST be forward slashes '/'") but there are a lot of bad zip generators... // Search "unzip mismatching "local" filename continuing with "central" filename version" on // the internet. // // I think I see the logic here : the central directory is used to display // content and the local directory is used to extract the files. Mixing / and \ // may be used to display \ to windows users and use / when extracting the files. // Unfortunately, this lead also to some issues : http://seclists.org/fulldisclosure/2009/Sep/394 this.fileNameLength = reader.readInt(2); localExtraFieldsLength = reader.readInt(2); // can't be sure this will be the same as the central dir // the fileName is stored as binary data, the handleUTF8 method will take care of the encoding. this.fileName = reader.readData(this.fileNameLength); reader.skip(localExtraFieldsLength); if (this.compressedSize === -1 || this.uncompressedSize === -1) { throw new Error("Bug or corrupted zip : didn't get enough information from the central directory " + "(compressedSize === -1 || uncompressedSize === -1)"); } compression = findCompression(this.compressionMethod); if (compression === null) { // no compression found throw new Error("Corrupted zip : compression " + utils.pretty(this.compressionMethod) + " unknown (inner file : " + utils.transformTo("string", this.fileName) + ")"); } this.decompressed = new CompressedObject(this.compressedSize, this.uncompressedSize, this.crc32, compression, reader.readData(this.compressedSize)); }, /** * Read the central part of a zip file and add the info in this object. * @param {DataReader} reader the reader to use. */ readCentralPart: function(reader) { this.versionMadeBy = reader.readInt(2); reader.skip(2); // this.versionNeeded = reader.readInt(2); this.bitFlag = reader.readInt(2); this.compressionMethod = reader.readString(2); this.date = reader.readDate(); this.crc32 = reader.readInt(4); this.compressedSize = reader.readInt(4); this.uncompressedSize = reader.readInt(4); var fileNameLength = reader.readInt(2); this.extraFieldsLength = reader.readInt(2); this.fileCommentLength = reader.readInt(2); this.diskNumberStart = reader.readInt(2); this.internalFileAttributes = reader.readInt(2); this.externalFileAttributes = reader.readInt(4); this.localHeaderOffset = reader.readInt(4); if (this.isEncrypted()) { throw new Error("Encrypted zip are not supported"); } // will be read in the local part, see the comments there reader.skip(fileNameLength); this.readExtraFields(reader); this.parseZIP64ExtraField(reader); this.fileComment = reader.readData(this.fileCommentLength); }, /** * Parse the external file attributes and get the unix/dos permissions. */ processAttributes: function () { this.unixPermissions = null; this.dosPermissions = null; var madeBy = this.versionMadeBy >> 8; // Check if we have the DOS directory flag set. // We look for it in the DOS and UNIX permissions // but some unknown platform could set it as a compatibility flag. this.dir = this.externalFileAttributes & 0x0010 ? true : false; if(madeBy === MADE_BY_DOS) { // first 6 bits (0 to 5) this.dosPermissions = this.externalFileAttributes & 0x3F; } if(madeBy === MADE_BY_UNIX) { this.unixPermissions = (this.externalFileAttributes >> 16) & 0xFFFF; // the octal permissions are in (this.unixPermissions & 0x01FF).toString(8); } // fail safe : if the name ends with a / it probably means a folder if (!this.dir && this.fileNameStr.slice(-1) === "/") { this.dir = true; } }, /** * Parse the ZIP64 extra field and merge the info in the current ZipEntry. * @param {DataReader} reader the reader to use. */ parseZIP64ExtraField: function() { if (!this.extraFields[0x0001]) { return; } // should be something, preparing the extra reader var extraReader = readerFor(this.extraFields[0x0001].value); // I really hope that these 64bits integer can fit in 32 bits integer, because js // won't let us have more. if (this.uncompressedSize === utils.MAX_VALUE_32BITS) { this.uncompressedSize = extraReader.readInt(8); } if (this.compressedSize === utils.MAX_VALUE_32BITS) { this.compressedSize = extraReader.readInt(8); } if (this.localHeaderOffset === utils.MAX_VALUE_32BITS) { this.localHeaderOffset = extraReader.readInt(8); } if (this.diskNumberStart === utils.MAX_VALUE_32BITS) { this.diskNumberStart = extraReader.readInt(4); } }, /** * Read the central part of a zip file and add the info in this object. * @param {DataReader} reader the reader to use. */ readExtraFields: function(reader) { var end = reader.index + this.extraFieldsLength, extraFieldId, extraFieldLength, extraFieldValue; if (!this.extraFields) { this.extraFields = {}; } while (reader.index + 4 < end) { extraFieldId = reader.readInt(2); extraFieldLength = reader.readInt(2); extraFieldValue = reader.readData(extraFieldLength); this.extraFields[extraFieldId] = { id: extraFieldId, length: extraFieldLength, value: extraFieldValue }; } reader.setIndex(end); }, /** * Apply an UTF8 transformation if needed. */ handleUTF8: function() { var decodeParamType = support.uint8array ? "uint8array" : "array"; if (this.useUTF8()) { this.fileNameStr = utf8.utf8decode(this.fileName); this.fileCommentStr = utf8.utf8decode(this.fileComment); } else { var upath = this.findExtraFieldUnicodePath(); if (upath !== null) { this.fileNameStr = upath; } else { // ASCII text or unsupported code page var fileNameByteArray = utils.transformTo(decodeParamType, this.fileName); this.fileNameStr = this.loadOptions.decodeFileName(fileNameByteArray); } var ucomment = this.findExtraFieldUnicodeComment(); if (ucomment !== null) { this.fileCommentStr = ucomment; } else { // ASCII text or unsupported code page var commentByteArray = utils.transformTo(decodeParamType, this.fileComment); this.fileCommentStr = this.loadOptions.decodeFileName(commentByteArray); } } }, /** * Find the unicode path declared in the extra field, if any. * @return {String} the unicode path, null otherwise. */ findExtraFieldUnicodePath: function() { var upathField = this.extraFields[0x7075]; if (upathField) { var extraReader = readerFor(upathField.value); // wrong version if (extraReader.readInt(1) !== 1) { return null; } // the crc of the filename changed, this field is out of date. if (crc32fn(this.fileName) !== extraReader.readInt(4)) { return null; } return utf8.utf8decode(extraReader.readData(upathField.length - 5)); } return null; }, /** * Find the unicode comment declared in the extra field, if any. * @return {String} the unicode comment, null otherwise. */ findExtraFieldUnicodeComment: function() { var ucommentField = this.extraFields[0x6375]; if (ucommentField) { var extraReader = readerFor(ucommentField.value); // wrong version if (extraReader.readInt(1) !== 1) { return null; } // the crc of the comment changed, this field is out of date. if (crc32fn(this.fileComment) !== extraReader.readInt(4)) { return null; } return utf8.utf8decode(extraReader.readData(ucommentField.length - 5)); } return null; } }; module.exports = ZipEntry;