datasign

#!/usr/bin/env node

/*
 * datasign - sign text or file
 *
 * Copyright (c) 2016 Kenji Urushima (kenji.urushima@gmail.com)
 *
 * This software is licensed under the terms of the MIT License.
 * https://kjur.github.io/jsrsasign/license
 *
 * The above copyright and license notice shall be 
 * included in all copies or substantial portions of the Software.
 * 
 * Please use '-h' option for this script usage.
 * ---------------------------------------------------------
 * DESCRIPTION
 *   This script signes a text or file data by specified private key
 *   and signature algorithm.
 *
 * USAGE
 *   % datasign aaa.txt a.prv a.sig
 *   % datasign aaa.txt a.prv a256.sig SHA256withRSA
 *   % datasign "test" a.prv test.sig
 *
 *   Resulted signature can also be verified by OpenSSL.
 *   % openssl dgst -sha1 -verify a.pub -signature a.sig aaa.txt
 */

var program = require('commander');
var rs = require('jsrsasign');
var rsu = require('jsrsasign-util');
var path = require('path');

program
  .version('1.0.0 (2016-Nov-19)')
  .usage('[options] <text or file> <private key> <output signature file> [sig alg]')
  .description('sign text or file with specified private key and sig algorithm.')
  .parse(process.argv);

if (program.args.length !== 3 && program.args.length !== 4)
  throw "wrong number of arguments";

var textOrFile = program.args[0];
var prvFile = program.args[1];
var outFile = program.args[2];
var hashAlg = "SHA1withRSA";
if (program.args.length === 4) hashAlg = program.args[3];

// 1. private key
var prvPEM = rsu.readFile(prvFile);
var prv = rs.KEYUTIL.getKey(prvPEM);
//console.log(prv);

// 2. data to be signed
var text;
try {
  text = rsu.readFile(textOrFile);
} catch(ex) {
  text = textOrFile;
}

var sig = new rs.KJUR.crypto.Signature({alg: hashAlg});
sig.init(prv);
sig.updateString(text);
var sigHex = sig.sign();
rsu.saveFileBinByHex(outFile, sigHex);
//console.log(sigHex);
console.log("successfully signed");