metamask-extension/app/scripts/background.js

const urlUtil = require('url')
const Dnode = require('dnode')
const eos = require('end-of-stream')
const extend = require('xtend')
const EthStore = require('eth-store')
const MetaMaskProvider = require('web3-provider-engine/zero.js')
const PortStream = require('./lib/port-stream.js')
const IdentityStore = require('./lib/idStore')
const createUnlockRequestNotification = require('./lib/notifications.js').createUnlockRequestNotification
const createTxNotification = require('./lib/notifications.js').createTxNotification
const createMsgNotification = require('./lib/notifications.js').createMsgNotification
const configManager = require('./lib/config-manager-singleton')
const messageManager = require('./lib/message-manager')
const setupMultiplex = require('./lib/stream-utils.js').setupMultiplex
const HostStore = require('./lib/remote-store.js').HostStore
const Web3 = require('web3')

//
// connect to other contexts
//

chrome.runtime.onConnect.addListener(connectRemote)
function connectRemote (remotePort) {
  var isMetaMaskInternalProcess = (remotePort.name === 'popup')
  var portStream = new PortStream(remotePort)
  if (isMetaMaskInternalProcess) {
    // communication with popup
    setupTrustedCommunication(portStream, 'MetaMask')
  } else {
    // communication with page
    var originDomain = urlUtil.parse(remotePort.sender.url).hostname
    setupUntrustedCommunication(portStream, originDomain)
  }
}

function setupUntrustedCommunication (connectionStream, originDomain) {
  // setup multiplexing
  var mx = setupMultiplex(connectionStream)
  // connect features
  setupProviderConnection(mx.createStream('provider'), originDomain)
  setupPublicConfig(mx.createStream('publicConfig'))
}

function setupTrustedCommunication (connectionStream, originDomain) {
  // setup multiplexing
  var mx = setupMultiplex(connectionStream)
  // connect features
  setupControllerConnection(mx.createStream('controller'))
  setupProviderConnection(mx.createStream('provider'), originDomain)
}

//
// state and network
//

var idStore = new IdentityStore()

var providerOpts = {
  rpcUrl: configManager.getCurrentRpcAddress(),
  // account mgmt
  getAccounts: function (cb) {
    var selectedAddress = idStore.getSelectedAddress()
    var result = selectedAddress ? [selectedAddress] : []
    cb(null, result)
  },
  // tx signing
  approveTransaction: newUnsignedTransaction,
  signTransaction: idStore.signTransaction.bind(idStore),
  // msg signing
  approveMessage: newUnsignedMessage,
  signMessage: idStore.signMessage.bind(idStore),
}
var provider = MetaMaskProvider(providerOpts)
var web3 = new Web3(provider)
idStore.web3 = web3
idStore.getNetwork()

// log new blocks
provider.on('block', function (block) {
  console.log('BLOCK CHANGED:', '#' + block.number.toString('hex'), '0x' + block.hash.toString('hex'))

  // Check network when restoring connectivity:
  if (idStore._currentState.network === 'loading') {
    idStore.getNetwork()
  }
})

provider.on('error', idStore.getNetwork.bind(idStore))

var ethStore = new EthStore(provider)
idStore.setStore(ethStore)

function getState () {
  var state = extend(
    ethStore.getState(),
    idStore.getState(),
    configManager.getConfig()
  )
  return state
}

//
// public store
//

// get init state
var initPublicState = extend(
  idStoreToPublic(idStore.getState()),
  configToPublic(configManager.getConfig())
)

var publicConfigStore = new HostStore(initPublicState)

// subscribe to changes
configManager.subscribe(function (state) {
  storeSetFromObj(publicConfigStore, configToPublic(state))
})
idStore.on('update', function (state) {
  storeSetFromObj(publicConfigStore, idStoreToPublic(state))
})

// idStore substate
function idStoreToPublic (state) {
  return {
    selectedAddress: state.selectedAddress,
  }
}
// config substate
function configToPublic (state) {
  return {
    provider: state.provider,
  }
}
// dump obj into store
function storeSetFromObj (store, obj) {
  Object.keys(obj).forEach(function (key) {
    store.set(key, obj[key])
  })
}

//
// remote features
//

function setupPublicConfig (stream) {
  var storeStream = publicConfigStore.createStream()
  stream.pipe(storeStream).pipe(stream)
}

function setupProviderConnection (stream, originDomain) {
  // decorate all payloads with origin domain
  stream.on('data', function onRpcRequest (request) {
    var payloads = Array.isArray(request) ? request : [request]
    payloads.forEach(function (payload) {
      // Append origin to rpc payload
      payload.origin = originDomain
      // Append origin to signature request
      if (payload.method === 'eth_sendTransaction') {
        payload.params[0].origin = originDomain
      } else if (payload.method === 'eth_sign') {
        payload.params.push({ origin: originDomain })
      }
    })
    // handle rpc request
    provider.sendAsync(request, function onPayloadHandled (err, response) {
      if (err) {
        return logger(err)
      }
      logger(null, request, response)
      try {
        stream.write(response)
      } catch (err) {
        logger(err)
      }
    })
  })

  function logger (err, request, response) {
    if (err) return console.error(err.stack)
    if (!request.isMetamaskInternal) {
      console.log(`RPC (${originDomain}):`, request, '->', response)
      if (response.error) console.error('Error in RPC response:\n' + response.error.message)
    }
  }
}

function setupControllerConnection (stream) {
  var dnode = Dnode({
    getState: function (cb) { cb(null, getState()) },
    setRpcTarget: setRpcTarget,
    setProviderType: setProviderType,
    useEtherscanProvider: useEtherscanProvider,
    agreeToDisclaimer: agreeToDisclaimer,
    // forward directly to idStore
    createNewVault: idStore.createNewVault.bind(idStore),
    recoverFromSeed: idStore.recoverFromSeed.bind(idStore),
    submitPassword: idStore.submitPassword.bind(idStore),
    setSelectedAddress: idStore.setSelectedAddress.bind(idStore),
    approveTransaction: idStore.approveTransaction.bind(idStore),
    cancelTransaction: idStore.cancelTransaction.bind(idStore),
    signMessage: idStore.signMessage.bind(idStore),
    cancelMessage: idStore.cancelMessage.bind(idStore),
    setLocked: idStore.setLocked.bind(idStore),
    clearSeedWordCache: idStore.clearSeedWordCache.bind(idStore),
    exportAccount: idStore.exportAccount.bind(idStore),
    revealAccount: idStore.revealAccount.bind(idStore),
    saveAccountLabel: idStore.saveAccountLabel.bind(idStore),
    tryPassword: idStore.tryPassword.bind(idStore),
    recoverSeed: idStore.recoverSeed.bind(idStore),
  })
  stream.pipe(dnode).pipe(stream)
  dnode.on('remote', function (remote) {
    // push updates to popup
    ethStore.on('update', sendUpdate)
    idStore.on('update', sendUpdate)
    // teardown on disconnect
    eos(stream, function unsubscribe () {
      ethStore.removeListener('update', sendUpdate)
    })
    function sendUpdate () {
      var state = getState()
      remote.sendUpdate(state)
    }
  })
}

//
// plugin badge text
//

idStore.on('update', updateBadge)

function updateBadge (state) {
  var label = ''
  var unconfTxs = configManager.unconfirmedTxs()
  var unconfTxLen = Object.keys(unconfTxs).length
  var unconfMsgs = messageManager.unconfirmedMsgs()
  var unconfMsgLen = Object.keys(unconfMsgs).length
  var count = unconfTxLen + unconfMsgLen
  if (count) {
    label = String(count)
  }
  chrome.browserAction.setBadgeText({ text: label })
  chrome.browserAction.setBadgeBackgroundColor({ color: '#506F8B' })
}

//
// Add unconfirmed Tx + Msg
//

function newUnsignedTransaction (txParams, onTxDoneCb) {
  var state = idStore.getState()
  if (!state.isUnlocked) {
    createUnlockRequestNotification({
      title: 'Account Unlock Request',
    })
    idStore.addUnconfirmedTransaction(txParams, onTxDoneCb, noop)
  } else {
    addUnconfirmedTx(txParams, onTxDoneCb)
  }
}

function newUnsignedMessage (msgParams, cb) {
  var state = idStore.getState()
  if (!state.isUnlocked) {
    createUnlockRequestNotification({
      title: 'Account Unlock Request',
    })
  } else {
    addUnconfirmedMsg(msgParams, cb)
  }
}

function addUnconfirmedTx (txParams, onTxDoneCb) {
  idStore.addUnconfirmedTransaction(txParams, onTxDoneCb, function (err, txData) {
    if (err) return onTxDoneCb(err)
    createTxNotification({
      title: 'New Unsigned Transaction',
      txParams: txParams,
      confirm: idStore.approveTransaction.bind(idStore, txData.id, noop),
      cancel: idStore.cancelTransaction.bind(idStore, txData.id),
    })
  })
}

function addUnconfirmedMsg (msgParams, cb) {
  var msgId = idStore.addUnconfirmedMessage(msgParams, cb)
  createMsgNotification({
    title: 'New Unsigned Message',
    msgParams: msgParams,
    confirm: idStore.approveMessage.bind(idStore, msgId, noop),
    cancel: idStore.cancelMessage.bind(idStore, msgId),
  })
}

//
// config
//

function agreeToDisclaimer (cb) {
  try {
    configManager.setConfirmed(true)
    cb()
  } catch (e) {
    cb(e)
  }
}

// called from popup
function setRpcTarget (rpcTarget) {
  configManager.setRpcTarget(rpcTarget)
  chrome.runtime.reload()
  idStore.getNetwork()
}

function setProviderType (type) {
  configManager.setProviderType(type)
  chrome.runtime.reload()
  idStore.getNetwork()
}

function useEtherscanProvider () {
  configManager.useEtherscanProvider()
  chrome.runtime.reload()
}

// util

function noop () {}