Finished requestPairingCode

src/Utils/auth-utils.ts

@@ -196,10 +196,11 @@ export const initAuthCreds = (): AuthenticationCreds => {
 	const identityKey = Curve.generateKeyPair()
 	return {
 		noiseKey: Curve.generateKeyPair(),
+		pairingEphemeralKeyPair: Curve.generateKeyPair(),
 		signedIdentityKey: identityKey,
 		signedPreKey: signedKeyPair(identityKey, 1),
 		registrationId: generateRegistrationId(),
-		advKeyPair: Curve.generateKeyPair(),
+		advSecretKey: randomBytes(32).toString('base64'),
 		processedHistoryMessages: [],
 		nextPreKeyId: 1,
 		firstUnuploadedPreKeyId: 1,
@@ -214,6 +215,6 @@ export const initAuthCreds = (): AuthenticationCreds => {
 		registered: false,
 		backupToken: randomBytes(20),
 		registration: {} as never,
-		pairingCode: undefined
+		pairingCode: undefined,
 	}
 }

src/Utils/crypto.ts

@@ -1,8 +1,8 @@
-import { createCipheriv, createDecipheriv, createHash, createHmac, randomBytes } from 'crypto'
+import {createCipheriv, createDecipheriv, createHash, createHmac, pbkdf2Sync, randomBytes} from 'crypto'
 import HKDF from 'futoin-hkdf'
 import * as libsignal from 'libsignal'
-import { KEY_BUNDLE_TYPE } from '../Defaults'
-import { KeyPair } from '../Types'
+import {KEY_BUNDLE_TYPE} from '../Defaults'
+import {KeyPair} from '../Types'
 
 /** prefix version byte to the pub keys, required for some curve crypto functions */
 export const generateSignalPubKey = (pubKey: Uint8Array | Buffer) => (
@@ -74,6 +74,16 @@ export function aesDecryptGCM(ciphertext: Uint8Array, key: Uint8Array, iv: Uint8
 	return Buffer.concat([ decipher.update(enc), decipher.final() ])
 }
 
+export function aesEncryptCTR(plaintext: Uint8Array, key: Uint8Array, iv: Uint8Array) {
+	const cipher = createCipheriv('aes-256-ctr', key, iv)
+	return Buffer.concat([cipher.update(plaintext), cipher.final()])
+}
+
+export function aesDecryptCTR(ciphertext: Uint8Array, key: Uint8Array, iv: Uint8Array) {
+	const decipher = createDecipheriv('aes-256-ctr', key, iv)
+	return Buffer.concat([decipher.update(ciphertext), decipher.final()])
+}
+
 /** decrypt AES 256 CBC; where the IV is prefixed to the buffer */
 export function aesDecrypt(buffer: Buffer, key: Buffer) {
 	return aesDecryptWithIV(buffer.slice(16, buffer.length), key, buffer.slice(0, 16))
@@ -114,4 +124,8 @@ export function md5(buffer: Buffer) {
 // HKDF key expansion
 export function hkdf(buffer: Uint8Array | Buffer, expandedLength: number, info: { salt?: Buffer, info?: string }) {
 	return HKDF(!Buffer.isBuffer(buffer) ? Buffer.from(buffer) : buffer, expandedLength, info)
+}
+
+export function derivePairingCodeKey(pairingCode: string, salt: Buffer) {
+	return pbkdf2Sync(pairingCode, salt, 2 << 16, 32, 'sha256')
 }

src/Utils/generics.ts

@@ -411,31 +411,4 @@ export function bytesToCrockford(buffer: Buffer): string {
 	}
 
 	return crockford.join('')
-}
-
-export async function derivePairingKey(pairingCode: string, salt: Buffer) {
-	const encoded = new TextEncoder().encode(pairingCode)
-	const cryptoKey = await crypto.subtle.importKey(
-		'raw',
-		encoded,
-		{
-			name: 'PBKDF2'
-		},
-		!1,
-		[
-			'deriveKey'
-		]
-	)
-	return await crypto.subtle.deriveKey({
-		name: 'PBKDF2',
-		hash: 'SHA-256',
-		salt: salt,
-		iterations: 2 << 16
-	}, cryptoKey, {
-		name: 'AES-CTR',
-		length: 256
-	}, false, [
-		'encrypt',
-		'decrypt'
-	])
 }

src/Utils/validate-connection.ts

@@ -117,7 +117,7 @@ export const generateRegistrationNode = (
 
 export const configureSuccessfulPairing = (
 	stanza: BinaryNode,
-	{ advKeyPair, signedIdentityKey, signalIdentities }: Pick<AuthenticationCreds, 'advKeyPair' | 'signedIdentityKey' | 'signalIdentities'>
+	{ advSecretKey, signedIdentityKey, signalIdentities }: Pick<AuthenticationCreds, 'advSecretKey' | 'signedIdentityKey' | 'signalIdentities'>
 ) => {
 	const msgId = stanza.attrs.id
 
@@ -137,7 +137,7 @@ export const configureSuccessfulPairing = (
 
 	const { details, hmac } = proto.ADVSignedDeviceIdentityHMAC.decode(deviceIdentityNode.content as Buffer)
 	// check HMAC matches
-	const advSign = hmacSign(details, advKeyPair.public)
+	const advSign = hmacSign(details, Buffer.from(advSecretKey, 'base64'))
 	if(Buffer.compare(hmac, advSign) !== 0) {
 		throw new Boom('Invalid account signature')
 	}
@@ -208,8 +208,7 @@ export const encodeSignedDeviceIdentity = (
 		account.accountSignatureKey = null
 	}
 
-	const accountEnc = proto.ADVSignedDeviceIdentity
+	return proto.ADVSignedDeviceIdentity
 		.encode(account)
 		.finish()
-	return accountEnc
 }