fork-openpgpjs/src/packet/public_key.js
2016-02-03 20:24:54 +07:00

225 lines
6.4 KiB
JavaScript

// GPG4Browsers - An OpenPGP implementation in javascript
// Copyright (C) 2011 Recurity Labs GmbH
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 3.0 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
/**
* Implementation of the Key Material Packet (Tag 5,6,7,14)<br/>
* <br/>
* {@link http://tools.ietf.org/html/rfc4880#section-5.5|RFC4480 5.5}:
* A key material packet contains all the information about a public or
* private key. There are four variants of this packet type, and two
* major versions. Consequently, this section is complex.
* @requires crypto
* @requires enums
* @requires type/keyid
* @requires type/mpi
* @requires util
* @module packet/public_key
*/
module.exports = PublicKey;
var util = require('../util.js'),
type_mpi = require('../type/mpi.js'),
type_keyid = require('../type/keyid.js'),
enums = require('../enums.js'),
crypto = require('../crypto');
/**
* @constructor
*/
function PublicKey() {
this.tag = enums.packet.publicKey;
this.version = 4;
/** Key creation date.
* @type {Date} */
this.created = new Date();
/** A list of multiprecision integers
* @type {module:type/mpi} */
this.mpi = [];
/** Public key algorithm
* @type {module:enums.publicKey} */
this.algorithm = 'rsa_sign';
// time in days (V3 only)
this.expirationTimeV3 = 0;
/**
* Fingerprint in lowercase hex
* @type {String}
*/
this.fingerprint = null;
/**
* Keyid
* @type {module:type/keyid}
*/
this.keyid = null;
}
/**
* Internal Parser for public keys as specified in {@link http://tools.ietf.org/html/rfc4880#section-5.5.2|RFC 4880 section 5.5.2 Public-Key Packet Formats}
* called by read_tag&lt;num&gt;
* @param {Uint8Array} bytes Input array to read the packet from
* @return {Object} This object with attributes set by the parser
*/
PublicKey.prototype.read = function (bytes) {
var pos = 0;
// A one-octet version number (3 or 4).
this.version = bytes[pos++];
if (this.version == 3 || this.version == 4) {
// - A four-octet number denoting the time that the key was created.
this.created = util.readDate(bytes.subarray(pos, pos + 4));
pos += 4;
if (this.version == 3) {
// - A two-octet number denoting the time in days that this key is
// valid. If this number is zero, then it does not expire.
this.expirationTimeV3 = util.readNumber(bytes.subarray(pos, pos + 2));
pos += 2;
}
// - A one-octet number denoting the public-key algorithm of this key.
this.algorithm = enums.read(enums.publicKey, bytes[pos++]);
var mpicount = crypto.getPublicMpiCount(this.algorithm);
this.mpi = [];
var bmpi = bytes.subarray(pos, bytes.length);
var p = 0;
for (var i = 0; i < mpicount && p < bmpi.length; i++) {
this.mpi[i] = new type_mpi();
p += this.mpi[i].read(bmpi.subarray(p, bmpi.length));
if (p > bmpi.length) {
throw new Error('Error reading MPI @:' + p);
}
}
return p + 6;
} else {
throw new Error('Version ' + this.version + ' of the key packet is unsupported.');
}
};
/**
* Alias of read()
* @see module:packet/public_key~PublicKey#read
*/
PublicKey.prototype.readPublicKey = PublicKey.prototype.read;
/**
* Same as write_private_key, but has less information because of
* public key.
* @return {Uint8Array} OpenPGP packet body contents,
*/
PublicKey.prototype.write = function () {
var arr = [];
// Version
arr.push(new Uint8Array([this.version]));
arr.push(util.writeDate(this.created));
if (this.version == 3) {
arr.push(util.writeNumber(this.expirationTimeV3, 2));
}
arr.push(new Uint8Array([enums.write(enums.publicKey, this.algorithm)]));
var mpicount = crypto.getPublicMpiCount(this.algorithm);
for (var i = 0; i < mpicount; i++) {
arr.push(this.mpi[i].write());
}
return util.concatUint8Array(arr);
};
/**
* Alias of write()
* @see module:packet/public_key~PublicKey#write
*/
PublicKey.prototype.writePublicKey = PublicKey.prototype.write;
/**
* Write an old version packet - it's used by some of the internal routines.
*/
PublicKey.prototype.writeOld = function () {
var bytes = this.writePublicKey();
return util.concatUint8Array([new Uint8Array([0x99]), util.writeNumber(bytes.length, 2), bytes]);
};
/**
* Calculates the key id of the key
* @return {String} A 8 byte key id
*/
PublicKey.prototype.getKeyId = function () {
if (this.keyid) {
return this.keyid;
}
this.keyid = new type_keyid();
if (this.version == 4) {
this.keyid.read(util.str2Uint8Array(util.hex2bin(this.getFingerprint()).substr(12, 8)));
} else if (this.version == 3) {
var arr = this.mpi[0].write();
this.keyid.read(arr.subarray(arr.length - 8, arr.length));
}
return this.keyid;
};
/**
* Calculates the fingerprint of the key
* @return {String} A string containing the fingerprint in lowercase hex
*/
PublicKey.prototype.getFingerprint = function () {
if (this.fingerprint) {
return this.fingerprint;
}
var toHash = '';
if (this.version == 4) {
toHash = this.writeOld();
this.fingerprint = util.Uint8Array2str(crypto.hash.sha1(toHash));
} else if (this.version == 3) {
var mpicount = crypto.getPublicMpiCount(this.algorithm);
for (var i = 0; i < mpicount; i++) {
toHash += this.mpi[i].toBytes();
}
this.fingerprint = util.Uint8Array2str(crypto.hash.md5(util.str2Uint8Array(toHash)));
}
this.fingerprint = util.hexstrdump(this.fingerprint);
return this.fingerprint;
};
/**
* Returns bit size of key
* @return {int} Number of bits
*/
PublicKey.prototype.getBitSize = function () {
return this.mpi[0].byteLength() * 8;
};
/**
* Fix custom types after cloning
*/
PublicKey.prototype.postCloneTypeFix = function() {
for (var i = 0; i < this.mpi.length; i++) {
this.mpi[i] = type_mpi.fromClone(this.mpi[i]);
}
if (this.keyid) {
this.keyid = type_keyid.fromClone(this.keyid);
}
};