jsrsasign

The 'jsrsasign' (RSA-Sign JavaScript Library) is an opensource free pure JavaScript cryptographic library supports RSA/RSAPSS/ECDSA/DSA signing/validation, ASN.1, PKCS#1/5/8 private/public key, X.509 certificate, CRL, CMS SignedData, TimeStamp and CAdES and JSON Web Signature(JWS)/Token(JWT)/Key(JWK).

Public page is http://kjur.github.com/jsrsasign .

DIFFERENCE WITH CRYPTO MODULE

Here is the difference between bundled 'Crypto' module and this 'jsrsasign' module.

• Crypto module
  • fast
  • works only on Node.js
  • OpenSSL based
  • lacking ASN.1 functionality
  • provides symmetric ciphers
  • lacking RSAPSS signing
• jsrsasign module
  • slow
  • implemented in pure JavaScript
  • works on both Node.js(server) and browsers(client)
  • provides ASN.1 parsing/generation functionality
  • lacking symmetric ciphers
  • provides RSAPSS signing
  • also provides support for JSON Web Signatures (JWS) and JSON Web Token (JWT)

CONCLUDED THIRD-PARTY LIBRARIES

• CryptoJS: for symmetric cipher, hash, mac, PBKDF (BSD License)
• BitCoinJS: for ECDSA (MIT License)
• OpenPGP.js: for DSA (LGPL License)
• Tom Wu's jsbn: for BigInteger, RSA encryption and EC (BSD License)
• Yahoo YUI: for class inheritance (BSD License)
• json-sans-eval: secure JSON parser (Apache License)

AVAILABLE CLASSES AND METHODS

Most of the classes and methods defined in jsrsasign and jsjws are available in this jsrsasign npm module.

After loading the module,

> var r = require('jsrsasign');

You can refer name spaces, classes, methods and functions by following variables:

• r.BigInteger - BigInteger class
• r.RSAKey - RSAKey class
• r.ECDSA - KJUR.crypto.ECDSA class
• r.DSA - KJUR.crypto.DSA class
• r.Signature - KJUR.crypto.Signature class
• r.MessageDigest - KJUR.crypto.MessageDigest class
• r.Mac - KJUR.crypto.Mac class
• r.KEYUTIL - KEYUTIL class
• r.ASN1HEX - ASN1HEX class
• r.crypto - KJUR.crypto name space
• r.asn1 - KJUR.asn1 name space
• r.jws - KJUR.jws name space

Please see API reference in the above links.

EXAMPLE(1) SIGNATURE

Loading encrypted PKCS#5 private key:

> var fs = require('fs');
> var pem = fs.readFileSync('z1.prv.p5e.pem', 'binary');
> var prvKey = a.KEYUTIL.getKey(pem, 'passwd');

Sign string 'aaa' with the loaded private key:

> var sig = new a.Signature({alg: 'SHA1withRSA'});
> sig.init(prvKey);
> sig.updateString('aaa');
> var sigVal = sig.sign();
> sigVal
'd764dcacb...'