node-rsa

What is node-rsa?

The node-rsa package is a Node.js library for RSA key generation, encryption, and decryption. It provides a simple and easy-to-use API for working with RSA keys and performing cryptographic operations.

What are node-rsa's main functionalities?

Key Generation

This feature allows you to generate a new RSA key pair. The code sample demonstrates how to create a 512-bit RSA key pair and export the public and private keys.

const NodeRSA = require('node-rsa');
const key = new NodeRSA({b: 512});
const publicKey = key.exportKey('public');
const privateKey = key.exportKey('private');
console.log('Public Key:', publicKey);
console.log('Private Key:', privateKey);

Encryption

This feature allows you to encrypt data using the RSA public key. The code sample shows how to encrypt a string message and output the encrypted data in base64 format.

const NodeRSA = require('node-rsa');
const key = new NodeRSA({b: 512});
const encrypted = key.encrypt('Hello, World!', 'base64');
console.log('Encrypted:', encrypted);

Decryption

This feature allows you to decrypt data using the RSA private key. The code sample demonstrates how to decrypt the previously encrypted message and output the original string.

const NodeRSA = require('node-rsa');
const key = new NodeRSA({b: 512});
const encrypted = key.encrypt('Hello, World!', 'base64');
const decrypted = key.decrypt(encrypted, 'utf8');
console.log('Decrypted:', decrypted);

Signing

This feature allows you to sign data using the RSA private key. The code sample shows how to create a digital signature for a string message and output the signature in base64 format.

const NodeRSA = require('node-rsa');
const key = new NodeRSA({b: 512});
const signature = key.sign('Hello, World!', 'base64');
console.log('Signature:', signature);

Verification

This feature allows you to verify a digital signature using the RSA public key. The code sample demonstrates how to verify the signature of a message and output whether the signature is valid.

const NodeRSA = require('node-rsa');
const key = new NodeRSA({b: 512});
const signature = key.sign('Hello, World!', 'base64');
const isVerified = key.verify('Hello, World!', signature, 'utf8', 'base64');
console.log('Verified:', isVerified);

Other packages similar to node-rsa

crypto

The 'crypto' module is a built-in Node.js module that provides cryptographic functionality, including RSA key generation, encryption, and decryption. It is more comprehensive and versatile compared to node-rsa, but also more complex to use.

ursa

The 'ursa' package is another Node.js library for RSA public/private key encryption and decryption. It offers similar functionalities to node-rsa but is less actively maintained and has fewer features.

node-forge

The 'node-forge' package is a comprehensive library for implementing various cryptographic operations, including RSA. It provides more features and flexibility compared to node-rsa, but with a steeper learning curve.

README

Node-RSA

Node.js RSA library
Based on jsbn library from Tom Wu http://www-cs-students.stanford.edu/~tjw/jsbn/

• Pure JavaScript
• No needed OpenSSL
• Generating keys
• Supports long messages for encrypt/decrypt
• Signing and verifying

Example

var NodeRSA = require('node-rsa');
var key = new NodeRSA({b: 512});

var text = 'Hello RSA!';
var encrypted = key.encrypt(text, 'base64');
console.log('encrypted: ', encrypted);
var decrypted = key.decrypt(encrypted, 'utf8');
console.log('decrypted: ', decrypted);

Installing

npm install node-rsa

Testing

npm test

Work environment

This library developed and tested primary for Node.js, but it still can work in browsers with browserify.

Usage

Create instance

var NodeRSA = require('node-rsa');

var key = new NodeRSA([key], [options]);

key - parameters of a generated key or the key in PEM format.
options - additional settings

• environment - working environment, 'browser' or 'node'. Default autodetect.
• signingAlgorithm - hash algorithm used for signing and verifying. Can be 'sha1', 'sha256', 'md5'. Default 'sha256'.

"Empty" key

var key = new NodeRSA();

Generate new key 512bit-length and with public exponent 65537

var key = new NodeRSA({b: 512});

Load key from PEM string

var key = new NodeRSA('-----BEGIN RSA PRIVATE KEY-----\n'+
                      'MIIBOQIBAAJAVY6quuzCwyOWzymJ7C4zXjeV/232wt2ZgJZ1kHzjI73wnhQ3WQcL\n'+
                      'DFCSoi2lPUW8/zspk0qWvPdtp6Jg5Lu7hwIDAQABAkBEws9mQahZ6r1mq2zEm3D/\n'+
                      'VM9BpV//xtd6p/G+eRCYBT2qshGx42ucdgZCYJptFoW+HEx/jtzWe74yK6jGIkWJ\n'+
                      'AiEAoNAMsPqwWwTyjDZCo9iKvfIQvd3MWnmtFmjiHoPtjx0CIQCIMypAEEkZuQUi\n'+
                      'pMoreJrOlLJWdc0bfhzNAJjxsTv/8wIgQG0ZqI3GubBxu9rBOAM5EoA4VNjXVigJ\n'+
                      'QEEk1jTkp8ECIQCHhsoq90mWM/p9L5cQzLDWkTYoPI49Ji+Iemi2T5MRqwIgQl07\n'+
                      'Es+KCn25OKXR/FJ5fu6A6A+MptABL3r8SEjlpLc=\n'+
                      '-----END RSA PRIVATE KEY-----');

Also you can use next methods:

key.generateKeyPair([bits], [exp]);
key.loadFromPEM(pem_string|buffer_contains_pem);

bits - key size in bits. 2048 by default.
exp - public exponent. 65537 by default.

Export keys

key.getPrivatePEM();
key.getPublicPEM();

Properties

Key testing

key.isPrivate();
key.isPublic([strict]);

strict - if true method will return false if key pair have private exponent. Default false.

key.isEmpty();

Return true if key pair doesn't have any data.

Key info

key.getKeySize();

Return key size in bits.

key.getMaxMessageSize();

Return max data size for encrypt in bytes.

Encrypting/decrypting

key.encrypt(buffer, [encoding], [source_encoding]);

Return encrypted data.
buffer - data for encrypting, may be string, Buffer, or any object/array. Arrays and objects will encoded to JSON string first.
encoding - encoding for output result, may be 'buffer', 'binary', 'hex' or 'base64'. Default 'buffer'.
source_encoding - source encoding, works only with string buffer. Can take standard Node.js Buffer encodings (hex, utf8, base64, etc). 'utf8' by default.

key.decrypt(buffer, [encoding]);

Return decrypted data.
buffer - data for decrypting. Takes Buffer object or base64 encoded string.
encoding - encoding for result string. Can also take 'buffer' for raw Buffer object, or 'json' for automatic JSON.parse result. Default 'buffer'.

Signing/Verifying

key.sign(buffer, [encoding], [source_encoding]);

Return signature for buffer. All the arguments are the same as for encrypt method.

key.verify(buffer, signature, [source_encoding], [signature_encoding])

Return result of check, true or false.
buffer - data for check, same as encrypt method.
signature - signature for check, result of sign method.
source_encoding - same as for encrypt method.
signature_encoding - encoding of given signature. May be 'buffer', 'binary', 'hex' or 'base64'. Default 'buffer'.

Contributing

Questions, comments, bug reports, and pull requests are all welcome.

Changelog

0.1.54

• Added support for loading PEM key from Buffer (fs.readFileSync output)
• Added isEmpty() method

0.1.52

• Improve work with not properly trimming PEM strings

0.1.50

• Implemented native js signing and verifying for browsers
• options.signingAlgorithm now takes only hash-algorithm name
• Added .getKeySize() and .getMaxMessageSize() methods
• .loadFromPublicPEM and .loadFromPrivatePEM methods marked as private

0.1.40

• Added signing/verifying

0.1.30

• Added long message support

License for NodeRSA.js

Copyright (c) 2014 rzcoder
All Rights Reserved.

BSD

Licensing for code used in rsa.js and jsbn.js

Copyright (c) 2003-2005 Tom Wu
All Rights Reserved.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

IN NO EVENT SHALL TOM WU BE LIABLE FOR ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

In addition, the following condition applies:

All redistributions must retain an intact copy of this copyright notice and disclaimer.