You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

339 lines
11 KiB
JavaScript

var Utils = require("../util"),
Constants = Utils.Constants;
/* The central directory file header */
module.exports = function () {
var _verMade = 20, // v2.0
_version = 10, // v1.0
_flags = 0,
_method = 0,
_time = 0,
_crc = 0,
_compressedSize = 0,
_size = 0,
_fnameLen = 0,
_extraLen = 0,
_comLen = 0,
_diskStart = 0,
_inattr = 0,
_attr = 0,
_offset = 0;
_verMade |= Utils.isWin ? 0x0a00 : 0x0300;
// Set EFS flag since filename and comment fields are all by default encoded using UTF-8.
// Without it file names may be corrupted for other apps when file names use unicode chars
_flags |= Constants.FLG_EFS;
var _dataHeader = {};
function setTime(val) {
val = new Date(val);
_time =
(((val.getFullYear() - 1980) & 0x7f) << 25) | // b09-16 years from 1980
((val.getMonth() + 1) << 21) | // b05-08 month
(val.getDate() << 16) | // b00-04 hour
// 2 bytes time
(val.getHours() << 11) | // b11-15 hour
(val.getMinutes() << 5) | // b05-10 minute
(val.getSeconds() >> 1); // b00-04 seconds divided by 2
}
setTime(+new Date());
return {
get made() {
return _verMade;
},
set made(val) {
_verMade = val;
},
get version() {
return _version;
},
set version(val) {
_version = val;
},
get flags() {
return _flags;
},
set flags(val) {
_flags = val;
},
get method() {
return _method;
},
set method(val) {
switch (val) {
case Constants.STORED:
this.version = 10;
case Constants.DEFLATED:
default:
this.version = 20;
}
_method = val;
},
get time() {
return new Date(((_time >> 25) & 0x7f) + 1980, ((_time >> 21) & 0x0f) - 1, (_time >> 16) & 0x1f, (_time >> 11) & 0x1f, (_time >> 5) & 0x3f, (_time & 0x1f) << 1);
},
set time(val) {
setTime(val);
},
get crc() {
return _crc;
},
set crc(val) {
_crc = Math.max(0, val) >>> 0;
},
get compressedSize() {
return _compressedSize;
},
set compressedSize(val) {
_compressedSize = Math.max(0, val) >>> 0;
},
get size() {
return _size;
},
set size(val) {
_size = Math.max(0, val) >>> 0;
},
get fileNameLength() {
return _fnameLen;
},
set fileNameLength(val) {
_fnameLen = val;
},
get extraLength() {
return _extraLen;
},
set extraLength(val) {
_extraLen = val;
},
get commentLength() {
return _comLen;
},
set commentLength(val) {
_comLen = val;
},
get diskNumStart() {
return _diskStart;
},
set diskNumStart(val) {
_diskStart = Math.max(0, val) >>> 0;
},
get inAttr() {
return _inattr;
},
set inAttr(val) {
_inattr = Math.max(0, val) >>> 0;
},
get attr() {
return _attr;
},
set attr(val) {
_attr = Math.max(0, val) >>> 0;
},
// get Unix file permissions
get fileAttr() {
return _attr ? (((_attr >>> 0) | 0) >> 16) & 0xfff : 0;
},
get offset() {
return _offset;
},
set offset(val) {
_offset = Math.max(0, val) >>> 0;
},
get encripted() {
return (_flags & 1) === 1;
},
get entryHeaderSize() {
return Constants.CENHDR + _fnameLen + _extraLen + _comLen;
},
get realDataOffset() {
return _offset + Constants.LOCHDR + _dataHeader.fnameLen + _dataHeader.extraLen;
},
get dataHeader() {
return _dataHeader;
},
loadDataHeaderFromBinary: function (/*Buffer*/ input) {
var data = input.slice(_offset, _offset + Constants.LOCHDR);
// 30 bytes and should start with "PK\003\004"
if (data.readUInt32LE(0) !== Constants.LOCSIG) {
throw new Error(Utils.Errors.INVALID_LOC);
}
_dataHeader = {
// version needed to extract
version: data.readUInt16LE(Constants.LOCVER),
// general purpose bit flag
flags: data.readUInt16LE(Constants.LOCFLG),
// compression method
method: data.readUInt16LE(Constants.LOCHOW),
// modification time (2 bytes time, 2 bytes date)
time: data.readUInt32LE(Constants.LOCTIM),
// uncompressed file crc-32 value
crc: data.readUInt32LE(Constants.LOCCRC),
// compressed size
compressedSize: data.readUInt32LE(Constants.LOCSIZ),
// uncompressed size
size: data.readUInt32LE(Constants.LOCLEN),
// filename length
fnameLen: data.readUInt16LE(Constants.LOCNAM),
// extra field length
extraLen: data.readUInt16LE(Constants.LOCEXT)
};
},
loadFromBinary: function (/*Buffer*/ data) {
// data should be 46 bytes and start with "PK 01 02"
if (data.length !== Constants.CENHDR || data.readUInt32LE(0) !== Constants.CENSIG) {
throw new Error(Utils.Errors.INVALID_CEN);
}
// version made by
_verMade = data.readUInt16LE(Constants.CENVEM);
// version needed to extract
_version = data.readUInt16LE(Constants.CENVER);
// encrypt, decrypt flags
_flags = data.readUInt16LE(Constants.CENFLG);
// compression method
_method = data.readUInt16LE(Constants.CENHOW);
// modification time (2 bytes time, 2 bytes date)
_time = data.readUInt32LE(Constants.CENTIM);
// uncompressed file crc-32 value
_crc = data.readUInt32LE(Constants.CENCRC);
// compressed size
_compressedSize = data.readUInt32LE(Constants.CENSIZ);
// uncompressed size
_size = data.readUInt32LE(Constants.CENLEN);
// filename length
_fnameLen = data.readUInt16LE(Constants.CENNAM);
// extra field length
_extraLen = data.readUInt16LE(Constants.CENEXT);
// file comment length
_comLen = data.readUInt16LE(Constants.CENCOM);
// volume number start
_diskStart = data.readUInt16LE(Constants.CENDSK);
// internal file attributes
_inattr = data.readUInt16LE(Constants.CENATT);
// external file attributes
_attr = data.readUInt32LE(Constants.CENATX);
// LOC header offset
_offset = data.readUInt32LE(Constants.CENOFF);
},
dataHeaderToBinary: function () {
// LOC header size (30 bytes)
var data = Buffer.alloc(Constants.LOCHDR);
// "PK\003\004"
data.writeUInt32LE(Constants.LOCSIG, 0);
// version needed to extract
data.writeUInt16LE(_version, Constants.LOCVER);
// general purpose bit flag
data.writeUInt16LE(_flags, Constants.LOCFLG);
// compression method
data.writeUInt16LE(_method, Constants.LOCHOW);
// modification time (2 bytes time, 2 bytes date)
data.writeUInt32LE(_time, Constants.LOCTIM);
// uncompressed file crc-32 value
data.writeUInt32LE(_crc, Constants.LOCCRC);
// compressed size
data.writeUInt32LE(_compressedSize, Constants.LOCSIZ);
// uncompressed size
data.writeUInt32LE(_size, Constants.LOCLEN);
// filename length
data.writeUInt16LE(_fnameLen, Constants.LOCNAM);
// extra field length
data.writeUInt16LE(_extraLen, Constants.LOCEXT);
return data;
},
entryHeaderToBinary: function () {
// CEN header size (46 bytes)
var data = Buffer.alloc(Constants.CENHDR + _fnameLen + _extraLen + _comLen);
// "PK\001\002"
data.writeUInt32LE(Constants.CENSIG, 0);
// version made by
data.writeUInt16LE(_verMade, Constants.CENVEM);
// version needed to extract
data.writeUInt16LE(_version, Constants.CENVER);
// encrypt, decrypt flags
data.writeUInt16LE(_flags, Constants.CENFLG);
// compression method
data.writeUInt16LE(_method, Constants.CENHOW);
// modification time (2 bytes time, 2 bytes date)
data.writeUInt32LE(_time, Constants.CENTIM);
// uncompressed file crc-32 value
data.writeUInt32LE(_crc, Constants.CENCRC);
// compressed size
data.writeUInt32LE(_compressedSize, Constants.CENSIZ);
// uncompressed size
data.writeUInt32LE(_size, Constants.CENLEN);
// filename length
data.writeUInt16LE(_fnameLen, Constants.CENNAM);
// extra field length
data.writeUInt16LE(_extraLen, Constants.CENEXT);
// file comment length
data.writeUInt16LE(_comLen, Constants.CENCOM);
// volume number start
data.writeUInt16LE(_diskStart, Constants.CENDSK);
// internal file attributes
data.writeUInt16LE(_inattr, Constants.CENATT);
// external file attributes
data.writeUInt32LE(_attr, Constants.CENATX);
// LOC header offset
data.writeUInt32LE(_offset, Constants.CENOFF);
// fill all with
data.fill(0x00, Constants.CENHDR);
return data;
},
toJSON: function () {
const bytes = function (nr) {
return nr + " bytes";
};
return {
made: _verMade,
version: _version,
flags: _flags,
method: Utils.methodToString(_method),
time: this.time,
crc: "0x" + _crc.toString(16).toUpperCase(),
compressedSize: bytes(_compressedSize),
size: bytes(_size),
fileNameLength: bytes(_fnameLen),
extraLength: bytes(_extraLen),
commentLength: bytes(_comLen),
diskNumStart: _diskStart,
inAttr: _inattr,
attr: _attr,
offset: _offset,
entryHeaderSize: bytes(Constants.CENHDR + _fnameLen + _extraLen + _comLen)
};
},
toString: function () {
return JSON.stringify(this.toJSON(), null, "\t");
}
};
};