BexLedger.js

'use strict'

const utils = require(require('path').resolve(__dirname, './utils'))

const BexLedgerWallet = function (comm) {
  this.comm = comm
  this.comm.setScrambleKey('w0w')
}

/* eslint-disable node/no-deprecated-api */
BexLedgerWallet.prototype.getAddress_async = function (path) {
  const splitPath = utils.splitPath(path)
  const buffer = new Buffer(5 + 1 + splitPath.length * 4)
  buffer[0] = 0xe0
  buffer[1] = 0x02
  buffer[2] = 0x00
  buffer[3] = 0x40
  buffer[4] = 1 + splitPath.length * 4
  buffer[5] = splitPath.length
  splitPath.forEach((element, index) => {
    buffer.writeUInt32BE(element, 6 + 4 * index)
  })
  return this.comm.exchange(buffer.toString('hex'), [0x9000]).then((response) => {
    const result = {}
    // console.log(response)
    response = Buffer.from(response, 'hex')
    const publicKeyLength = response[0]
    const addressLength = response[1 + publicKeyLength]
    result['publicKey'] = response.slice(1, 1 + publicKeyLength).toString('hex')
    result['address'] = response.slice(1 + publicKeyLength + 1, 1 + publicKeyLength + 1 + addressLength).toString('ascii')
    return result
  })
}

BexLedgerWallet.prototype.signTransaction_async = function (path, rawTxHex) {
  const splitPath = utils.splitPath(path)
  const rawTx = Buffer.from(rawTxHex, 'hex')
  const self = this

  let data1, data2
  const data1HeaderLength = new Buffer(2)
  const data2HeaderLength = new Buffer(1)
  const pathLength = 4 * splitPath.length + 1
  const apdus = []
  let p1
  let response

  path = new Buffer(pathLength - 1)
  splitPath.forEach((element, index) => {
    path.writeUInt32BE(element, 4 * index)
  })

  if (rawTx.length > 255 - pathLength) {
    data1 = rawTx.slice(0, 255 - pathLength)
    data2 = rawTx.slice(255 - pathLength)
    p1 = '00'
  } else {
    data1 = rawTx
    p1 = '80'
  }

  // console.log(data1.toString("hex"))

  data1HeaderLength[0] = pathLength + data1.length
  data1HeaderLength[1] = splitPath.length
  if (data2) {
    data2HeaderLength[0] = data2.length
  }

  // console.log("> ",data1_headerlength.toString("hex"))
  // console.log("> ",path.toString("hex"))

  apdus.push('e004' + p1 + '40' + data1HeaderLength.toString('hex') + path.toString('hex') + data1.toString('hex'))
  if (data2) {
    apdus.push('e0048140' + data2HeaderLength.toString('hex') + data2.toString('hex'))
  }
  // console.log(apdus)
  return utils.foreach(apdus, (apdu) => {
    // console.log(apdu)
    return self.comm.exchange(apdu, [0x9000]).then((apduResponse) => {
      response = apduResponse
    // console.log(apduResponse)
    })
  }).then(() => {
    // console.log(response)
    const result = {}
    result.signature = response.substring(0, response.length - 4)
    return result
  })
}

BexLedgerWallet.prototype.getAppConfiguration_async = function () {
  const buffer = new Buffer(5)
  buffer[0] = 0xe0
  buffer[1] = 0x06
  buffer[2] = 0x00
  buffer[3] = 0x00
  buffer[4] = 0x00
  return this.comm.exchange(buffer.toString('hex'), [0x9000]).then((response) => {
    const result = {}
    response = Buffer.from(response, 'hex')
    result['arbitraryDataEnabled'] = (response[0] & 0x01)
    result['version'] = '' + response[1] + '.' + response[2] + '.' + response[3]
    return result
  })
}

BexLedgerWallet.prototype.signPersonalMessage_async = function (path, messageHex) {
  const splitPath = utils.splitPath(path)
  let offset = 0
  const message = Buffer.from(messageHex, 'hex')
  const apdus = []
  let response = []
  const self = this
  while (offset !== message.length) {
    const maxChunkSize = (offset === 0 ? (150 - 1 - splitPath.length * 4 - 4) : 150)
    const chunkSize = (offset + maxChunkSize > message.length ? message.length - offset : maxChunkSize)
    const buffer = new Buffer(offset === 0 ? 5 + 1 + splitPath.length * 4 + 4 + chunkSize : 5 + chunkSize)
    buffer[0] = 0xe0
    buffer[1] = 0x08
    buffer[2] = (offset === 0 ? 0x00 : 0x80)
    buffer[3] = 0x40
    buffer[4] = (offset === 0 ? 1 + splitPath.length * 4 + 4 + chunkSize : chunkSize)
    if (offset === 0) {
      buffer[5] = splitPath.length
      splitPath.forEach((element, index) => {
        buffer.writeUInt32BE(element, 6 + 4 * index)
      })
      buffer.writeUInt32BE(message.length, 6 + 4 * splitPath.length)
      message.copy(buffer, 6 + 4 * splitPath.length + 4, offset, offset + chunkSize)
    } else {
      message.copy(buffer, 5, offset, offset + chunkSize)
    }
    apdus.push(buffer.toString('hex'))
    offset += chunkSize
  }
  return utils.foreach(apdus, (apdu) => {
    return self.comm.exchange(apdu, [0x9000]).then((apduResponse) => {
      response = apduResponse
    })
  }).then(() => {
    response = Buffer.from(response, 'hex')
    const result = {}
    result['v'] = response[0]
    result['r'] = response.slice(1, 1 + 32).toString('hex')
    result['s'] = response.slice(1 + 32, 1 + 32 + 32).toString('hex')
    return result
  })
}
/* eslint-enable node/no-deprecated-api */

module.exports = BexLedgerWallet