J-PAKE TypeScript Implementation

A TypeScript implementation of the Password Authenticated Key Exchange by Juggling (J-PAKE) protocol based on RFC 8236.

Documentation: https://boelensman1.github.io/jpake/

Features

• Full implementation of the J-PAKE protocol
• Support for both two-round and three-pass variants
• Zero-knowledge proof verification using Schnorr signatures
• Built on the secp256k1 elliptic curve
• Written in TypeScript with strict type checking

Installation

npm install jpake-ts

Usage

Two-Round Implementation

import { JPake, deriveSFromPassword } from 'jpake-ts'

// Initialize participants
const alice = new JPake('Alice')
const bob = new JPake('Bob')

// Convert password to shared secret
const password = 'secretPassword123'
const s = deriveSFromPassword(password)

// Execute Round 1
const aliceRound1 = alice.round1()
const bobRound1 = bob.round1()

// Execute Round 2
const aliceRound2 = alice.round2(bobRound1, s, bob.userId)
const bobRound2 = bob.round2(aliceRound1, s, alice.userId)

// Exchange Round 2 results
alice.setRound2ResultFromBob(bobRound2)
bob.setRound2ResultFromBob(aliceRound2)

// Derive shared keys
const aliceSharedKey = alice.deriveSharedKey()
const bobSharedKey = bob.deriveSharedKey()

// Keys should be equal
console.log(
  Buffer.from(aliceSharedKey).toString() ===
    Buffer.from(bobSharedKey).toString(),
) // true

Three-Pass Implementation

import { JPakeThreePass, deriveSFromPassword } from 'jpake-ts'

// Initialize participants
const alice = new JPakeThreePass('Alice')
const bob = new JPakeThreePass('Bob')

// Convert password to shared secret
const password = 'secretPassword123'
const s = deriveSFromPassword(password)

// Pass 1: Alice → Bob
const alicePass1 = alice.pass1()

// Pass 2: Bob → Alice
const bobPass2 = bob.pass2(alicePass1, s, alice.userId)

// Pass 3: Alice → Bob
const alicePass3 = alice.pass3(bobPass2, s, bob.userId)
bob.receivePass3Results(alicePass3)

// Derive shared keys
const aliceSharedKey = alice.deriveSharedKey()
const bobSharedKey = bob.deriveSharedKey()

// Keys should be equal
console.log(
  Buffer.from(aliceSharedKey).toString() ===
    Buffer.from(bobSharedKey).toString(),
) // true

Security Considerations

1. This implementation is not resistant to timing attacks. In cryptographic contexts where timing attacks are a concern, additional mitigations should be implemented.
2. If using deriveSFromPassword the password should be strong and have sufficient entropy.

Development

# Install dependencies
make install

# Run tests
make test

# Run tests with coverage
make coverage

# Build
make build

# Lint
make lint

# Compile docs
make docs

License

MIT