Files
Baileys/src/WAConnection/1.Validation.ts
Adhiraj Singh 63dd136afa Move msgCount increment to generateMessageTag
Prevents duplicate tags from being sent
2021-01-24 17:25:49 +05:30

239 lines
10 KiB
TypeScript

import * as Curve from 'curve25519-js'
import * as Utils from './Utils'
import {WAConnection as Base} from './0.Base'
import { WAMetric, WAFlag, BaileysError, Presence, WAUser, WAInitResponse, WAOpenResult } from './Constants'
export class WAConnection extends Base {
/** Authenticate the connection */
protected async authenticate (reconnect?: string) {
// if no auth info is present, that is, a new session has to be established
// generate a client ID
if (!this.authInfo?.clientID) {
this.authInfo = { clientID: Utils.generateClientID() } as any
}
const canLogin = this.canLogin()
this.referenceDate = new Date () // refresh reference date
this.startDebouncedTimeout ()
const initQuery = (async () => {
const {ref, ttl} = await this.query({
json: ['admin', 'init', this.version, this.browserDescription, this.authInfo?.clientID, true],
expect200: true,
waitForOpen: false,
longTag: true,
requiresPhoneConnection: false,
startDebouncedTimeout: true
}) as WAInitResponse
if (!canLogin) {
this.stopDebouncedTimeout () // stop the debounced timeout for QR gen
this.generateKeysForAuth (ref, ttl)
}
})();
let loginTag: string
if (canLogin) {
// if we have the info to restore a closed session
const json = [
'admin',
'login',
this.authInfo?.clientToken,
this.authInfo?.serverToken,
this.authInfo?.clientID,
]
loginTag = this.generateMessageTag(true)
if (reconnect) json.push(...['reconnect', reconnect.replace('@s.whatsapp.net', '@c.us')])
else json.push ('takeover')
// send login every 10s
const sendLoginReq = () => {
if (!this.conn || this.conn?.readyState !== this.conn.OPEN) {
this.logger.warn('Received login timeout req when WS not open, ignoring...')
return
}
if (this.state === 'open') {
this.logger.warn('Received login timeout req when state=open, ignoring...')
return
}
this.logger.debug('sending login request')
this.sendJSON(json, loginTag)
this.initTimeout = setTimeout(sendLoginReq, 10_000)
}
sendLoginReq()
}
await initQuery
// wait for response with tag "s1"
let response = await Promise.race(
[
this.waitForMessage('s1', false, undefined),
loginTag && this.waitForMessage(loginTag, false, undefined)
]
.filter(Boolean)
)
this.startDebouncedTimeout()
this.initTimeout && clearTimeout (this.initTimeout)
this.initTimeout = null
if (response.status && response.status !== 200) {
throw new BaileysError(`Unexpected error in login`, { response, status: response.status })
}
// if its a challenge request (we get it when logging in)
if (response[1]?.challenge) {
await this.respondToChallenge(response[1].challenge)
response = await this.waitForMessage('s2', true)
}
const result = this.validateNewConnection(response[1])// validate the connection
if (result.user.jid !== this.user?.jid) {
result.isNewUser = true
// clear out old data
this.chats.clear()
this.contacts = {}
}
this.user = result.user
this.logger.info('validated connection successfully')
this.sendPostConnectQueries ()
this.logger.debug('sent init queries')
return result
}
/**
* Send the same queries WA Web sends after connect
*/
sendPostConnectQueries () {
this.sendBinary (['query', {type: 'contacts', epoch: '1'}, null], [ WAMetric.queryContact, WAFlag.ignore ])
this.sendBinary (['query', {type: 'chat', epoch: '1'}, null], [ WAMetric.queryChat, WAFlag.ignore ])
this.sendBinary (['query', {type: 'status', epoch: '1'}, null], [ WAMetric.queryStatus, WAFlag.ignore ])
this.sendBinary (['query', {type: 'quick_reply', epoch: '1'}, null], [ WAMetric.queryQuickReply, WAFlag.ignore ])
this.sendBinary (['query', {type: 'label', epoch: '1'}, null], [ WAMetric.queryLabel, WAFlag.ignore ])
this.sendBinary (['query', {type: 'emoji', epoch: '1'}, null], [ WAMetric.queryEmoji, WAFlag.ignore ])
this.sendBinary (['action', {type: 'set', epoch: '1'}, [['presence', {type: Presence.available}, null]] ], [ WAMetric.presence, WAFlag.available ])
}
/**
* Refresh QR Code
* @returns the new ref
*/
async requestNewQRCodeRef() {
const response = await this.query({
json: ['admin', 'Conn', 'reref'],
expect200: true,
waitForOpen: false,
longTag: true,
requiresPhoneConnection: false
})
return response as WAInitResponse
}
/**
* Once the QR code is scanned and we can validate our connection, or we resolved the challenge when logging back in
* @private
* @param {object} json
*/
private validateNewConnection(json) {
// set metadata: one's WhatsApp ID [cc][number]@s.whatsapp.net, name on WhatsApp, info about the phone
const onValidationSuccess = () => ({
user: {
jid: Utils.whatsappID(json.wid),
name: json.pushname,
phone: json.phone,
imgUrl: null
},
auth: this.authInfo
}) as WAOpenResult
if (!json.secret) {
// if we didn't get a secret, we don't need it, we're validated
if (json.clientToken && json.clientToken !== this.authInfo.clientToken) {
this.authInfo = { ...this.authInfo, clientToken: json.clientToken }
}
if (json.serverToken && json.serverToken !== this.authInfo.serverToken) {
this.authInfo = { ...this.authInfo, serverToken: json.serverToken }
}
return onValidationSuccess()
}
const secret = Buffer.from(json.secret, 'base64')
if (secret.length !== 144) {
throw new Error ('incorrect secret length received: ' + secret.length)
}
// generate shared key from our private key & the secret shared by the server
const sharedKey = Curve.sharedKey(this.curveKeys.private, secret.slice(0, 32))
// expand the key to 80 bytes using HKDF
const expandedKey = Utils.hkdf(sharedKey as Buffer, 80)
// perform HMAC validation.
const hmacValidationKey = expandedKey.slice(32, 64)
const hmacValidationMessage = Buffer.concat([secret.slice(0, 32), secret.slice(64, secret.length)])
const hmac = Utils.hmacSign(hmacValidationMessage, hmacValidationKey)
if (!hmac.equals(secret.slice(32, 64))) {
// if the checksums didn't match
throw new BaileysError ('HMAC validation failed', json)
}
// computed HMAC should equal secret[32:64]
// expandedKey[64:] + secret[64:] are the keys, encrypted using AES, that are used to encrypt/decrypt the messages recieved from WhatsApp
// they are encrypted using key: expandedKey[0:32]
const encryptedAESKeys = Buffer.concat([
expandedKey.slice(64, expandedKey.length),
secret.slice(64, secret.length),
])
const decryptedKeys = Utils.aesDecrypt(encryptedAESKeys, expandedKey.slice(0, 32))
// set the credentials
this.authInfo = {
encKey: decryptedKeys.slice(0, 32), // first 32 bytes form the key to encrypt/decrypt messages
macKey: decryptedKeys.slice(32, 64), // last 32 bytes from the key to sign messages
clientToken: json.clientToken,
serverToken: json.serverToken,
clientID: this.authInfo.clientID,
}
return onValidationSuccess()
}
/**
* When logging back in (restoring a previously closed session), WhatsApp may challenge one to check if one still has the encryption keys
* WhatsApp does that by asking for us to sign a string it sends with our macKey
*/
protected respondToChallenge(challenge: string) {
const bytes = Buffer.from(challenge, 'base64') // decode the base64 encoded challenge string
const signed = Utils.hmacSign(bytes, this.authInfo.macKey).toString('base64') // sign the challenge string with our macKey
const json = ['admin', 'challenge', signed, this.authInfo.serverToken, this.authInfo.clientID] // prepare to send this signed string with the serverToken & clientID
this.logger.info('resolving login challenge')
return this.query({json, expect200: true, waitForOpen: false, startDebouncedTimeout: true})
}
/** When starting a new session, generate a QR code by generating a private/public key pair & the keys the server sends */
protected generateKeysForAuth(ref: string, ttl?: number) {
this.curveKeys = Curve.generateKeyPair(Utils.randomBytes(32))
const publicKey = Buffer.from(this.curveKeys.public).toString('base64')
const qrLoop = ttl => {
const qr = [ref, publicKey, this.authInfo.clientID].join(',')
this.emit ('qr', qr)
this.initTimeout = setTimeout (async () => {
if (this.state === 'open') return
this.logger.debug ('regenerating QR')
try {
const {ref: newRef, ttl: newTTL} = await this.requestNewQRCodeRef()
ttl = newTTL
ref = newRef
} catch (error) {
this.logger.warn ({ error }, `error in QR gen`)
if (error.status === 429) { // too many QR requests
this.endConnection(error.message)
return
}
}
qrLoop (ttl)
}, ttl || 20_000) // default is 20s, on the off-chance ttl is not present
}
qrLoop (ttl)
}
}