294 lines
11 KiB
JavaScript
294 lines
11 KiB
JavaScript
|
"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;
|