zkl-crypto

Cryptographic functions provider and example repository.

This module provides encryption and decryption functions for handling both binary data and strings using public and private keys. It utilizes ecies-wasm for the underlying cryptographic operations.

Package available on npm: https://www.npmjs.com/package/@zklx/crypto

Functions

encryptFile(publicKey: Key, fileName: string, data: Uint8Array): Uint8Array

Encrypts the given binary data for the recipient using the public key. The file name is included in the encrypted data.

• publicKey: The recipient's public key.
• fileName: The name of the file being encrypted.
• data: The plaintext data as a Uint8Array.

Returns the ciphertext as a Uint8Array.

decryptFile(privateKey: Key, data: Uint8Array): { data: Uint8Array, fileName: string }

Decrypts the given ciphertext using the recipient's private key. Returns the decrypted data and the original file name.

• privateKey: The recipient's private key.
• data: The ciphertext data as a Uint8Array.

Returns an object containing the plaintext data and the original file name.

encryptString(publicKey: Key, string: string): string

Encrypts the given string for the recipient using their public key. Returns the ciphertext as a hexadecimal string.

• publicKey: The recipient's public key.
• string: The plaintext string.

decryptString(privateKey: Key, string: string): string

Decrypts the given ciphertext string (in hexadecimal format) using the recipient's private key. Returns the plaintext string.

• privateKey: The recipient's private key.
• string: The ciphertext string in hexadecimal format.

Usage

import { Key } from "@zklx/kds";
import { encryptString, decryptString, encryptFile, decryptFile } from "@zklx/crypto";

// Example usage:

const publicKey = new Key(/* ... */);
const privateKey = new Key(/* ... */);

// Encrypt a string
const plaintext = "Hello, World!";
const encryptedString = encryptString(publicKey, plaintext);

// Decrypt the string
const decryptedString = decryptString(privateKey, encryptedString);

console.log(decryptedString); // "Hello, World!"

// Encrypt binary data
const fileName = "document.txt";
const data = new Uint8Array([/* ... */]);
const encryptedData = encryptFile(publicKey, fileName, data);

// Decrypt the binary data
const { data: decryptedData, fileName: decryptedFileName } = decryptFile(privateKey, encryptedData);

console.log(decryptedFileName); // "document.txt"
console.log(decryptedData); // Uint8Array

Example

To launch the example webpage:

pnpm install
npx webpack # use npx, pnpm - webpack integration is broken

Error Handling

This module performs type checks on its inputs. It throws TypeError if arguments are not of the expected types. Additionally, the decryptString function issues a warning if the provided ciphertext string does not appear to be a valid hexadecimal string.

Notes

• The asHexString method is added to Uint8Array.prototype if it does not already exist. This method converts a Uint8Array to a hexadecimal string representation.
• Ensure that your public and private keys are instances of the Key class provided by zkl-kds/key.

License

This project is licensed under the GNU Lesser General Public License, version 2.1.

Authored by Yigid BALABAN, fyb@fybx.dev

2024 © zk-Lokomotive team

https://zk-lokomotive.xyz/