cryptomate

Ergonomic, zero-dependency crypto module wrapper for ECDSA and EdDSA signatures.

Key features of the module include:

• Generation of ECDSA and EdDSA key pairs.
• Conversion between PEM (Privacy-Enhanced Mail) and DER (Distinguished Encoding Rules) formats.
• Extraction of public key from a given private key.
• Message signing and verification using ECDSA and EdDSA algorithms.

Installation

To install cryptomate, use the following npm command:

npm i --save cryptomate

Quick Start

Here is an example demonstrating the use of the ECDSA functionality provided by this module:

const {ECDSA, EC_CURVE, Key, SignatureEncoding} = require('cryptomate');

// Generate an ECDSA key pair.
const ecdsa = ECDSA.withCurve(EC_CURVE.secp256k1).genKeyPair();

// Sign a message.
let message = "Hello, World!";
let signature = ecdsa.sign(message, SignatureEncoding.HEX);

// Verify the signature.
console.log(ecdsa.verify(message, signature)); // Outputs: true

// Export keys in PEM format.
let privateKeyPEM = ecdsa.toPEM(Key.privateKey);
let publicKeyPEM = ecdsa.toPEM(Key.publicKey);

// Import keys from PEM format.
let importedECDSA = ECDSA.withCurve(EC_CURVE.secp256k1).fromPEM(privateKeyPEM, Key.privateKey);

API Reference

ECDSA

ECDSA.withCurve(curve)

A factory method to construct an ECDSA object with a given elliptic curve.

Parameters

• curve - The elliptic curve to use. This can be one of the following values:
  • EC_CURVE.P_256 - NIST P-256 curve.
  • EC_CURVE.P_384 - NIST P-384 curve.
  • EC_CURVE.P_521 - NIST P-521 curve.
  • EC_CURVE.SECP256K1 - SECP256K1 curve.
  • EC_CURVE.SECP256R1 - SECP256R1 curve.
  • EC_CURVE.SECP384R1 - SECP384R1 curve.
  • EC_CURVE.SECP521R1 - SECP521R1 curve.
  • ...

Returns

An ECDSA object with the given elliptic curve.

ECDSA.genKeyPair()

Generates a new ECDSA key pair.

Returns

An ECDSA object with a newly generated key pair.

ECDSA.fromPEM(pem, keyType)

Constructs an ECDSA object from a given PEM string.

Parameters

• pem - The PEM string to construct the ECDSA object from.
• keyType - The type of key to construct. This can be one of the following values:
  • Key.privateKey - Private key.
  • Key.publicKey - Public key.

Returns

An ECDSA object with the given PEM string.

ECDSA.toPEM(keyType)

Converts the ECDSA object to a PEM string.

Parameters

• keyType - The type of key to convert. This can be one of the following values:
  • Key.privateKey - Private key.
  • Key.publicKey - Public key.

Returns

A PEM string representing the ECDSA object.

ECDSA.getPublicKey()

Extracts the public key from the ECDSA object.

Returns

A Buffer object containing the public key.

ECDSA.sign(message, encoding)

Signs a message using the ECDSA object.

Parameters

• message - The message to sign.
• encoding - The encoding of the message. This can be one of the following values:
  • SignatureEncoding.HEX - The message is encoded in hexadecimal format.
  • SignatureEncoding.BASE64 - The message is encoded in Base64 format.
  • SignatureEncoding.UTF8 - The message is encoded in UTF-8 format.
  • ...

Returns

A Buffer object containing the signature.

ECDSA.verify(message, signature, encoding)

Verifies a signature using the ECDSA object.

Parameters

• message - The message to verify.
• signature - The signature to verify.
• encoding - The encoding of the message. This can be one of the following values:
  • SignatureEncoding.HEX - The message is encoded in hexadecimal format.
  • SignatureEncoding.BASE64 - The message is encoded in Base64 format.
  • SignatureEncoding.UTF8 - The message is encoded in UTF-8 format.
  • ...

Returns

A boolean value indicating whether the signature is valid.

EdDSA

Please note that the EdDSA class shares similar method names and functionalities to the ECDSA class for key pair generation, signing and verifying messages, and importing/exporting keys in various formats. Refer to the ECDSA API documentation provided above for further details.

License

This project is licensed under the MIT License - see the LICENSE file for details.