code: function findOpenSslBin (opensslBin) {
    if (opensslBin) {
      if (!fs.existsSync(opensslBin)) {
        throw new DxlError('Unable to find openssl at: ' + opensslBin)
      }
    } else {
      opensslBin = which.sync('openssl', {nothrow: true})
      if (!opensslBin && (os.platform() === 'win32')) {
        opensslBin = DEFAULT_OPENSSL_WIN32_INSTALL_DIRS.reduce(
          function (acc, candidatePath) {
            candidatePath = path.join(candidatePath, 'openssl.exe')
            if (!acc && fs.existsSync(candidatePath)) {
              acc = candidatePath
            }
            return acc
          },
          null
        )
      }
      if (!opensslBin) {
        throw new DxlError('Unable to find openssl from system path')
      }
    }
    return opensslBin
  }
docs: Returns the first location found for the openssl executable.
  @param {String} [opensslBin=null] - If non-null and the named file exists,
  this value is returned.
  @returns {String} Path to the openssl executable.
  @throws {DxlError} If openssl cannot be found.