What is eciesjs?
The eciesjs npm package provides functionalities for Elliptic Curve Integrated Encryption Scheme (ECIES) using the secp256k1 curve. It allows for secure encryption and decryption of messages using elliptic curve cryptography.
What are eciesjs's main functionalities?
Key Generation
This feature allows you to generate a new private key and derive the corresponding public key using the secp256k1 curve.
const ecies = require('eciesjs');
const privateKey = ecies.generatePrivateKey();
const publicKey = ecies.getPublicKey(privateKey);
console.log('Private Key:', privateKey.toString('hex'));
console.log('Public Key:', publicKey.toString('hex'));
Encryption
This feature allows you to encrypt a message using a given public key. The encrypted message is returned as a Buffer.
const ecies = require('eciesjs');
const publicKey = '04bfcab2...'; // Replace with actual public key
const message = Buffer.from('Hello, world!');
const encrypted = ecies.encrypt(publicKey, message);
console.log('Encrypted Message:', encrypted.toString('hex'));
Decryption
This feature allows you to decrypt an encrypted message using a given private key. The decrypted message is returned as a Buffer.
const ecies = require('eciesjs');
const privateKey = 'c87509a1...'; // Replace with actual private key
const encryptedMessage = Buffer.from('...'); // Replace with actual encrypted message
const decrypted = ecies.decrypt(privateKey, encryptedMessage);
console.log('Decrypted Message:', decrypted.toString());
Other packages similar to eciesjs
eccrypto
The eccrypto package provides similar functionalities for elliptic curve cryptography, including key generation, encryption, and decryption. It also uses the secp256k1 curve and offers additional features like signing and verification of messages.
elliptic
The elliptic package is a comprehensive library for elliptic curve cryptography. It supports multiple curves, including secp256k1, and provides functionalities for key generation, encryption, decryption, signing, and verification. It is more versatile compared to eciesjs.
secp256k1
The secp256k1 package is a specialized library for the secp256k1 elliptic curve. It provides low-level cryptographic operations, including key generation, signing, and verification. It is more focused on performance and low-level operations compared to eciesjs.
eciesjs
Elliptic Curve Integrated Encryption Scheme for secp256k1/curve25519 in TypeScript.
This is the JavaScript/TypeScript version of eciespy with a built-in class-like secp256k1/curve25519 API, you may go there for detailed documentation and learn the mechanism under the hood.
If you want a WASM version to run directly in modern browsers or on some blockchains, check ecies-wasm
.
Install
npm install eciesjs
We recommend using the latest Node runtime although it's still possible to install on old versions.
Quick Start
Run the code below with npx ts-node
.
> import { encrypt, decrypt, PrivateKey } from 'eciesjs'
> const sk = new PrivateKey()
> const data = Buffer.from('hello world🌍')
> decrypt(sk.secret, encrypt(sk.publicKey.toHex(), data)).toString()
'hello world🌍'
See Configuration to control with more granularity.
API
encrypt(receiverRawPK: string | Uint8Array, msg: Uint8Array): Buffer
Parameters:
- receiverRawPK - Receiver's public key, hex string or buffer
- msg - Data to encrypt
Returns: Buffer
decrypt(receiverRawSK: string | Uint8Array, msg: Uint8Array): Buffer
Parameters:
- receiverRawSK - Receiver's private key, hex string or buffer
- msg - Data to decrypt
Returns: Buffer
PrivateKey
static fromHex(hex: string): PrivateKey;
constructor(secret?: Uint8Array);
toHex(): string;
encapsulate(pk: PublicKey): Uint8Array;
multiply(pk: PublicKey, compressed?: boolean): Uint8Array;
equals(other: PrivateKey): boolean;
get secret(): Buffer;
readonly publicKey: PublicKey;
private readonly data;
PublicKey
static fromHex(hex: string): PublicKey;
constructor(data: Uint8Array);
toHex(compressed?: boolean): string;
decapsulate(sk: PrivateKey): Uint8Array;
equals(other: PublicKey): boolean;
get uncompressed(): Buffer;
get compressed(): Buffer;
private readonly data;
Configuration
Following configurations are available.
- Elliptic curve: secp256k1 or curve25519 (x25519/ed25519)
- Ephemeral key format in the payload: compressed or uncompressed (only for secp256k1)
- Shared elliptic curve key format in the key derivation: compressed or uncompressed (only for secp256k1)
- Symmetric cipher algorithm: AES-256-GCM or XChaCha20-Poly1305
- Symmetric nonce length: 12 or 16 bytes (only for AES-256-GCM)
For compatibility, make sure different applications share the same configuration.
export type EllipticCurve = "secp256k1" | "x25519" | "ed25519";
export type SymmetricAlgorithm = "aes-256-gcm" | "xchacha20";
export type NonceLength = 12 | 16;
class Config {
ellipticCurve: EllipticCurve = "secp256k1";
isEphemeralKeyCompressed: boolean = false;
isHkdfKeyCompressed: boolean = false;
symmetricAlgorithm: SymmetricAlgorithm = "aes-256-gcm";
symmetricNonceLength: NonceLength = 16;
}
export const ECIES_CONFIG = new Config();
Elliptic curve configuration
On ellipticCurve = "x25519"
or ellipticCurve = "ed25519"
, x25519 (key exchange function on curve25519) or ed25519 (signature algorithm on curve25519) will be used for key exchange instead of secp256k1.
In this case, the payload would always be: 32 Bytes + Ciphered
regardless of isEphemeralKeyCompressed
.
If you don't know how to choose between x25519 and ed25519, just use the dedicated key exchange function x25519 for efficiency.
Secp256k1-specific configuration
On isEphemeralKeyCompressed = true
, the payload would be: 33 Bytes + Ciphered
instead of 65 Bytes + Ciphered
.
On isHkdfKeyCompressed = true
, the hkdf key would be derived from ephemeral public key (compressed) + shared public key (compressed)
instead of ephemeral public key (uncompressed) + shared public key (uncompressed)
.
Symmetric cipher configuration
On symmetricAlgorithm = "xchacha20"
, plaintext data would be encrypted with XChaCha20-Poly1305.
On symmetricNonceLength = 12
, the nonce of AES-256-GCM would be 12 bytes. XChaCha20-Poly1305's nonce is always 24 bytes regardless of symmetricNonceLength
.
Security Audit
Following dependencies are audited:
Changelog
See CHANGELOG.md.