RSA Signing and Verification in JavaScript
Kenji Urushima
Sep 25, 2010
The 'RSA-Sign JavaScript Library' is a open source free pure JavaScript implementation of
PKCS#1 v2.1 RSASSA-PKCS1-v1_5 RSA signing and validation algorithm.
DEMO
SOURCE CODES
The 'rsa-sign' library contains following source codes.
- rsa-sign.js - RSAKey class extension for RSA signing and verification.
- x509.js - X509 class to read subject public key from certificate.
- rsa-pem.js - RSAKey class extension to read PKCS#1 RSA private key PEM file
- asn1hex.js - simple ASN.1 parser to read hexadecimal encoded ASN.1 DER
LICENSE
The 'RSA-Sign JavaScript Library' is licensed under the terms of the MIT license
reproduced below.
How to sign
var rsa = new RSAKey();
rsa.readPrivateKeyFromPEMString(_PEM_PRIVATE_KEY_STRING_);
var hSig = rsa.signString("aaa", "sha1"); // sign a string "aaa" with key
How to verify signature
vr x509 = new X509();
x509.readCertPEM(_PEM_X509CERT_STRING_);
var result = x509.subjectPublicKeyRSA.verifyString("aaa", _HEX_SIGNATURE_);
How to add supported signature algorithms
The script "rsa-sign.js" currently supports SHA1withRSA and SHA256withRSA
signature algorithms. However you can extend other signature algorithms
such like MD5withRSA or SHA512withRSA by just specifying two variables in it.
_RSASIGN_DIHEAD['md5'] = "30..."; // Hexadecimal DigestInfo prefix for MD5
_RSASIGN_HASHHEXFUNC['md5'] = md5hex; // function which returns value in hex.
Required Third Party Source Codes
- Tom Wu's jsbn library - BigInteger and RSA
- base64.js - String encoder for Base64 and Hex
- jsbn.js - basic BigInteger class
- jsbn2.js - BigInteger class extension
- prng4.js - Random number generator
- rng.js - Random number generator
- rsa.js - RSAKey class for RSA public key encryption.
- rsa2.js - RSA class extension for RSA private key decryption.
-
Hash algorithm of JavaScript
- sha1.js - SHA1 algorithm
- sha256.js - SHA256 algorithm
NOTE: As for hash algorithm, you can use any other hash implementations.
The requirement is to provide a function which returns hexadecimal
string as the result.
Copyright © 2010 Kenji Urushima. All rights reserved.
CHANGES
- 2010-SEP-25 - Web page update
- 2010-JUN-03 - Initial release
