feat(waku-utils): Add utils for `Waku Handshake`

Partial solution for https://github.com/status-im/nimbus-gui/issues/91

libs/waku-utils/src/waku-utils.ts

@@ -0,0 +1,81 @@
+import debug from 'debug'
+
+import { randomBytes } from '@stablelib/random'
+import { HMACDRBG } from '@stablelib/hmac-drbg'
+
+import { LightNode } from '@waku/interfaces'
+import { bytesToHex } from '@waku/utils/bytes'
+import {
+  HandshakeResult,
+  WakuPairing,
+  X25519DHKey,
+  ResponderParameters,
+  NoiseSecureTransferEncoder,
+  NoiseSecureTransferDecoder,
+} from '@waku/noise'
+
+import { CustomHandshakeResult } from './handshake'
+
+const log = debug('nimbus-gui:waku:utils')
+
+export function getPairingObject(node: LightNode): WakuPairing {
+  const dhKey = new X25519DHKey()
+  const rng = new HMACDRBG()
+
+  const nimbusGUIStaticKey = dhKey.generateKeyPair()
+
+  const applicationName = 'nimbus-gui'
+  const applicationVersion = '0.0.0'
+  const shardIdAsBytes = randomBytes(16, rng)
+  const shardId = bytesToHex(shardIdAsBytes)
+
+  const pairingObj = new WakuPairing(
+    node.lightPush,
+    node.filter,
+    nimbusGUIStaticKey,
+    new ResponderParameters(applicationName, applicationVersion, shardId),
+  )
+
+  const pInfo = pairingObj.getPairingInfo()
+  log(`Initial messageNameTag: "${bytesToHex(pInfo.qrMessageNameTag)}"`)
+  log(`QR Code: "${pInfo.qrCode}"`)
+  log(`Content topic: "${pairingObj.contentTopic}"`)
+
+  return pairingObj
+}
+
+export async function scheduleHandshakeAuthConfirmation(
+  pairingObj: WakuPairing,
+) {
+  const authCode = await pairingObj.getAuthCode()
+  log('Auth code is: ' + authCode)
+  pairingObj.validateAuthCode(true)
+}
+
+export async function proceedHandshake(pairingObj: WakuPairing): Promise<{
+  encoder: NoiseSecureTransferEncoder
+  decoder: NoiseSecureTransferDecoder
+  handshakeResult: HandshakeResult
+}> {
+  const pExecute = pairingObj.execute(120000) // timeout after 2m
+  await scheduleHandshakeAuthConfirmation(pairingObj)
+  log("Authcode confirmed")
+  const [encoder] = await pExecute
+  const handshakeResult = pairingObj.getHandshakeResult()
+  handshakeResult ? log('Handshake successful') : log('Handshake failed')
+
+  const customHandshakeResult = new CustomHandshakeResult(
+    handshakeResult.getCSOutbound(),
+    handshakeResult.getCSInbound(),
+    handshakeResult.nametagsInbound,
+    handshakeResult.nametagsOutbound,
+    handshakeResult.rs,
+    handshakeResult.h,
+  )
+
+  const decoder = new NoiseSecureTransferDecoder(
+    pairingObj.contentTopic,
+    customHandshakeResult,
+  )
+  return { encoder, decoder, handshakeResult: customHandshakeResult }
+}