SSI Crypto

The ssi-crypto package provides cryptographic primitives for Self-Sovereign Identity (SSI) systems. It supports key generation, signing, verification, and key management operations using industry-standard algorithms like Ed25519 and Secp256k1.

Installation

Install the package via NPM:

npm install @blockialabs/ssi-crypto

Key Components

Core Classes

• KeyManager: Manages cryptographic keys including creation, rotation, import/export operations.
• Signer: Provides signing and verification functionality.
• Key: Represents cryptographic key pairs with support for Ed25519 and Secp256k1.

Algorithms

• Ed25519Algorithm: Implementation of Ed25519 digital signature algorithm.
• Secp256k1Algorithm: Implementation of Secp256k1 elliptic curve cryptography.
• SigningAlgorithmFactory: Factory for creating algorithm instances.

Storage

• VaultKeyStore: Secure key storage implementation using the SSI storage abstraction.
• KeyRecord: Data structure for storing key metadata.

Interfaces

• IKeyManager: Interface for key management operations.
• ISigner: Interface for signing and verification operations.
• IKeyStore: Interface for key storage operations.
• ISigningAlgorithm: Interface for cryptographic algorithms.

Basic Usage

1. Setup Key Storage

Initialize the key store and algorithm factory.

import { VaultKeyStore, SigningAlgorithmFactory } from '@blockialabs/ssi-crypto';
import { MemoryStorage } from '@blockialabs/ssi-storage';

// Setup storage (you can use any IStorage implementation)
const storage = new MemoryStorage<KeyRecord>();
const keyStore = new VaultKeyStore(storage);

// Setup algorithm factory
const algorithmFactory = new SigningAlgorithmFactory();

2. Initialize Key Manager

Create a key manager instance.

import { KeyManager } from '@blockialabs/ssi-crypto';

const keyManager = new KeyManager(keyStore, algorithmFactory);

3. Initialize Signer

Create a signer instance.

import { Signer } from '@blockialabs/ssi-crypto';

const signer = new Signer(keyManager, algorithmFactory);

4. Create a Key

Generate a new cryptographic key.

const key = await signer.createKey('Ed25519');
console.log('Created key with ID:', key.kid);

5. Sign a Message

Sign a message using the created key.

const message = new TextEncoder().encode('Hello, World!');
const signature = await signer.sign(message, key);
console.log('Signature:', signature);

6. Verify a Signature

Verify the signature against the original message.

const isValid = await signer.verify(signature, message, key);
console.log('Signature is valid:', isValid);

Building

Run nx build ssi-crypto to build the library.

Running unit tests

Run nx test ssi-crypto to execute the unit tests via Jest.

Running lint

Run nx lint ssi-crypto to check if there are lint errors.

See LICENSE.