var util = require('util'); var zlib = require('zlib'); var Stream = require('stream'); var binary = require('binary'); var Promise = require('bluebird'); var PullStream = require('./PullStream'); var NoopStream = require('./NoopStream'); var BufferStream = require('./BufferStream'); var parseExtraField = require('./parseExtraField'); var Buffer = require('./Buffer'); var parseDateTime = require('./parseDateTime'); // Backwards compatibility for node versions < 8 if (!Stream.Writable || !Stream.Writable.prototype.destroy) Stream = require('readable-stream'); var endDirectorySignature = Buffer.alloc(4); endDirectorySignature.writeUInt32LE(0x06054b50, 0); function Parse(opts) { if (!(this instanceof Parse)) { return new Parse(opts); } var self = this; self._opts = opts || { verbose: false }; PullStream.call(self, self._opts); self.on('finish',function() { self.emit('close'); }); self._readRecord().catch(function(e) { if (!self.__emittedError || self.__emittedError !== e) self.emit('error',e); }); } util.inherits(Parse, PullStream); Parse.prototype._readRecord = function () { var self = this; return self.pull(4).then(function(data) { if (data.length === 0) return; var signature = data.readUInt32LE(0); if (signature === 0x34327243) { return self._readCrxHeader(); } if (signature === 0x04034b50) { return self._readFile(); } else if (signature === 0x02014b50) { self.__ended = true; return self._readCentralDirectoryFileHeader(); } else if (signature === 0x06054b50) { return self._readEndOfCentralDirectoryRecord(); } else if (self.__ended) { return self.pull(endDirectorySignature).then(function() { return self._readEndOfCentralDirectoryRecord(); }); } else self.emit('error', new Error('invalid signature: 0x' + signature.toString(16))); }); }; Parse.prototype._readCrxHeader = function() { var self = this; return self.pull(12).then(function(data) { self.crxHeader = binary.parse(data) .word32lu('version') .word32lu('pubKeyLength') .word32lu('signatureLength') .vars; return self.pull(self.crxHeader.pubKeyLength + self.crxHeader.signatureLength); }).then(function(data) { self.crxHeader.publicKey = data.slice(0,self.crxHeader.pubKeyLength); self.crxHeader.signature = data.slice(self.crxHeader.pubKeyLength); self.emit('crx-header',self.crxHeader); return self._readRecord(); }); }; Parse.prototype._readFile = function () { var self = this; return self.pull(26).then(function(data) { var vars = binary.parse(data) .word16lu('versionsNeededToExtract') .word16lu('flags') .word16lu('compressionMethod') .word16lu('lastModifiedTime') .word16lu('lastModifiedDate') .word32lu('crc32') .word32lu('compressedSize') .word32lu('uncompressedSize') .word16lu('fileNameLength') .word16lu('extraFieldLength') .vars; vars.lastModifiedDateTime = parseDateTime(vars.lastModifiedDate, vars.lastModifiedTime); if (self.crxHeader) vars.crxHeader = self.crxHeader; return self.pull(vars.fileNameLength).then(function(fileNameBuffer) { var fileName = fileNameBuffer.toString('utf8'); var entry = Stream.PassThrough(); var __autodraining = false; entry.autodrain = function() { __autodraining = true; var draining = entry.pipe(NoopStream()); draining.promise = function() { return new Promise(function(resolve, reject) { draining.on('finish',resolve); draining.on('error',reject); }); }; return draining; }; entry.buffer = function() { return BufferStream(entry); }; entry.path = fileName; entry.props = {}; entry.props.path = fileName; entry.props.pathBuffer = fileNameBuffer; entry.props.flags = { "isUnicode": vars.flags & 0x11 }; entry.type = (vars.uncompressedSize === 0 && /[\/\\]$/.test(fileName)) ? 'Directory' : 'File'; if (self._opts.verbose) { if (entry.type === 'Directory') { console.log(' creating:', fileName); } else if (entry.type === 'File') { if (vars.compressionMethod === 0) { console.log(' extracting:', fileName); } else { console.log(' inflating:', fileName); } } } return self.pull(vars.extraFieldLength).then(function(extraField) { var extra = parseExtraField(extraField, vars); entry.vars = vars; entry.extra = extra; self.emit('entry', entry); if (self._readableState.pipesCount) self.push(entry); if (self._opts.verbose) console.log({ filename:fileName, vars: vars, extra: extra }); var fileSizeKnown = !(vars.flags & 0x08) || vars.compressedSize > 0, eof; entry.__autodraining = __autodraining; // expose __autodraining for test purposes var inflater = (vars.compressionMethod && !__autodraining) ? zlib.createInflateRaw() : Stream.PassThrough(); if (fileSizeKnown) { entry.size = vars.uncompressedSize; eof = vars.compressedSize; } else { eof = Buffer.alloc(4); eof.writeUInt32LE(0x08074b50, 0); } self.stream(eof) .pipe(inflater) .on('error',function(err) { self.emit('error',err);}) .pipe(entry) .on('finish', function() { return fileSizeKnown ? self._readRecord() : self._processDataDescriptor(entry); }); return null; // This prevents bluebird from throwing "promise created but not returned" warnings }); }); }); }; Parse.prototype._processDataDescriptor = function (entry) { var self = this; self.pull(16).then(function(data) { var vars = binary.parse(data) .word32lu('dataDescriptorSignature') .word32lu('crc32') .word32lu('compressedSize') .word32lu('uncompressedSize') .vars; entry.size = vars.uncompressedSize; self._readRecord(); }); }; Parse.prototype._readCentralDirectoryFileHeader = function () { var self = this; self.pull(42).then(function(data) { var vars = binary.parse(data) .word16lu('versionMadeBy') .word16lu('versionsNeededToExtract') .word16lu('flags') .word16lu('compressionMethod') .word16lu('lastModifiedTime') .word16lu('lastModifiedDate') .word32lu('crc32') .word32lu('compressedSize') .word32lu('uncompressedSize') .word16lu('fileNameLength') .word16lu('extraFieldLength') .word16lu('fileCommentLength') .word16lu('diskNumber') .word16lu('internalFileAttributes') .word32lu('externalFileAttributes') .word32lu('offsetToLocalFileHeader') .vars; return self.pull(vars.fileNameLength).then(function(fileName) { vars.fileName = fileName.toString('utf8'); return self.pull(vars.extraFieldLength); }) .then(function(extraField) { return self.pull(vars.fileCommentLength); }) .then(function(fileComment) { return self._readRecord(); }); }); }; Parse.prototype._readEndOfCentralDirectoryRecord = function() { var self = this; self.pull(18).then(function(data) { var vars = binary.parse(data) .word16lu('diskNumber') .word16lu('diskStart') .word16lu('numberOfRecordsOnDisk') .word16lu('numberOfRecords') .word32lu('sizeOfCentralDirectory') .word32lu('offsetToStartOfCentralDirectory') .word16lu('commentLength') .vars; self.pull(vars.commentLength).then(function(comment) { comment = comment.toString('utf8'); self.end(); self.push(null); }); }); }; Parse.prototype.promise = function() { var self = this; return new Promise(function(resolve,reject) { self.on('finish',resolve); self.on('error',reject); }); }; module.exports = Parse;