fork-openpgpjs/src/crypto/signature.js
2016-02-04 00:37:00 +07:00

115 lines
4.0 KiB
JavaScript

/**
* @requires util
* @requires crypto/hash
* @requires crypto/pkcs1
* @requires crypto/public_key
* @module crypto/signature */
'use strict';
var util = require('../util'),
publicKey = require('./public_key'),
pkcs1 = require('./pkcs1.js');
module.exports = {
/**
*
* @param {module:enums.publicKey} algo public Key algorithm
* @param {module:enums.hash} hash_algo Hash algorithm
* @param {Array<module:type/mpi>} msg_MPIs Signature multiprecision integers
* @param {Array<module:type/mpi>} publickey_MPIs Public key multiprecision integers
* @param {Uint8Array} data Data on where the signature was computed on.
* @return {Boolean} true if signature (sig_data was equal to data over hash)
*/
verify: function(algo, hash_algo, msg_MPIs, publickey_MPIs, data) {
var m;
data = util.Uint8Array2str(data);
switch (algo) {
case 1:
// RSA (Encrypt or Sign) [HAC]
case 2:
// RSA Encrypt-Only [HAC]
case 3:
// RSA Sign-Only [HAC]
var rsa = new publicKey.rsa();
var n = publickey_MPIs[0].toBigInteger();
var k = publickey_MPIs[0].byteLength();
var e = publickey_MPIs[1].toBigInteger();
m = msg_MPIs[0].toBigInteger();
var EM = rsa.verify(m, e, n);
var EM2 = pkcs1.emsa.encode(hash_algo, data, k);
return EM.compareTo(EM2) === 0;
case 16:
// Elgamal (Encrypt-Only) [ELGAMAL] [HAC]
throw new Error("signing with Elgamal is not defined in the OpenPGP standard.");
case 17:
// DSA (Digital Signature Algorithm) [FIPS186] [HAC]
var dsa = new publicKey.dsa();
var s1 = msg_MPIs[0].toBigInteger();
var s2 = msg_MPIs[1].toBigInteger();
var p = publickey_MPIs[0].toBigInteger();
var q = publickey_MPIs[1].toBigInteger();
var g = publickey_MPIs[2].toBigInteger();
var y = publickey_MPIs[3].toBigInteger();
m = data;
var dopublic = dsa.verify(hash_algo, s1, s2, m, p, q, g, y);
return dopublic.compareTo(s1) === 0;
default:
throw new Error('Invalid signature algorithm.');
}
},
/**
* Create a signature on data using the specified algorithm
* @param {module:enums.hash} hash_algo hash Algorithm to use (See {@link http://tools.ietf.org/html/rfc4880#section-9.4|RFC 4880 9.4})
* @param {module:enums.publicKey} algo Asymmetric cipher algorithm to use (See {@link http://tools.ietf.org/html/rfc4880#section-9.1|RFC 4880 9.1})
* @param {Array<module:type/mpi>} publicMPIs Public key multiprecision integers
* of the private key
* @param {Array<module:type/mpi>} secretMPIs Private key multiprecision
* integers which is used to sign the data
* @param {Uint8Array} data Data to be signed
* @return {Array<module:type/mpi>}
*/
sign: function(hash_algo, algo, keyIntegers, data) {
data = util.Uint8Array2str(data);
var m;
switch (algo) {
case 1:
// RSA (Encrypt or Sign) [HAC]
case 2:
// RSA Encrypt-Only [HAC]
case 3:
// RSA Sign-Only [HAC]
var rsa = new publicKey.rsa();
var d = keyIntegers[2].toBigInteger();
var n = keyIntegers[0].toBigInteger();
m = pkcs1.emsa.encode(hash_algo,
data, keyIntegers[0].byteLength());
return util.str2Uint8Array(rsa.sign(m, d, n).toMPI());
case 17:
// DSA (Digital Signature Algorithm) [FIPS186] [HAC]
var dsa = new publicKey.dsa();
var p = keyIntegers[0].toBigInteger();
var q = keyIntegers[1].toBigInteger();
var g = keyIntegers[2].toBigInteger();
var x = keyIntegers[4].toBigInteger();
m = data;
var result = dsa.sign(hash_algo, m, g, p, q, x);
return util.str2Uint8Array(result[0].toString() + result[1].toString());
case 16:
// Elgamal (Encrypt-Only) [ELGAMAL] [HAC]
throw new Error('Signing with Elgamal is not defined in the OpenPGP standard.');
default:
throw new Error('Invalid signature algorithm.');
}
}
};