RSA OAEP Encryption

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The purpose of this project is to provide a pure JavaScript implementation of RSA encryption in an environment that does not support the Web Crypto API.

Thanks to node-forge, this project was forked from it and the following modifications and changes were made:

• Rewrite using TypeScript.
• Delete all nodejs-only codes.
• Only the encryption function using the RSA-OAEP algorithm is retained, and all other codes are deleted. It means that PKCS1-v1_5 is not supported.
• The hash algorithm only supports SHA1 SHA-256 SHA-384 SHA-512 to be consistent with the Web Crypto API.
• The return value of the encrypt method is changed to ArrayBuffer to be consistent with the Web Crypto API.
• The code is almost 100% covered and tree-shake friendly.

Installation

# via pnpm
pnpm add rsa-oaep-encryption
# or via yarn
yarn add rsa-oaep-encryption
# or just from npm
npm install --save rsa-oaep-encryption
# via JSR
jsr add @happy-js/rsa-oaep-encryption
# for deno
deno add @happy-js/rsa-oaep-encryption
# for bun
bunx jsr add @happy-js/rsa-oaep-encryption

Examples

import { importPublicKey, sha256 } from 'rsa-oaep-encryption';

const PUBLIC_KEY = `-----BEGIN PUBLIC KEY-----
xxxxx
-----END PUBLIC KEY-----`;
const encryptedData = importPublicKey(PUBLIC_KEY).encrypt('some data', sha256.create()); // or sha1 sha384 sha512

In an environment that supports the Web Crypto API, this is equivalent to the following code:

const keyData = base64ToBuffer(PUBLIC_KEY.replace(/(-----(BEGIN|END) PUBLIC KEY-----|\s)/g, '')); // base64ToBuffer needs to be implemented
const publicKey = await crypto.subtle.importKey(
    'spki',
    keyData,
    {
        name: 'RSA-OAEP',
        hash: 'SHA-256',
    },
    false,
    [
        'encrypt',
    ]
);
const encryptedData = await crypto.subtle.encrypt(
    {
        name: 'RSA-OAEP',
    },
    publicKey,
    new TextEncoder().encode('some data')
);

Of course, you can also use the exported SHA methods to perform SHA calculations separately in an environment that does not support the Web Crypto API.

Like this:

import { sha1 } from 'rsa-oaep-encryption';

const sha1Str = sha1.create().update('some data').digest().toHex();

Docs