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'use strict'
const dnsPacket = require('..')
const net = require('net')
var response = null
var expectedLength = 0
function getRandomInt (min, max) {
return Math.floor(Math.random() * (max - min + 1)) + min
}
const buf = dnsPacket.streamEncode({
type: 'query',
id: getRandomInt(1, 65534),
flags: dnsPacket.RECURSION_DESIRED,
questions: [{
type: 'A',
name: 'google.com'
}]
})
const client = new net.Socket()
client.connect(53, '8.8.8.8', function () {
console.log('Connected')
client.write(buf)
})
client.on('data', function (data) {
console.log('Received response: %d bytes', data.byteLength)
if (response == null) {
if (data.byteLength > 1) {
const plen = data.readUInt16BE(0)
expectedLength = plen
if (plen < 12) {
throw new Error('below DNS minimum packet length')
}
response = Buffer.from(data)
}
} else {
response = Buffer.concat([response, data])
}
if (response.byteLength >= expectedLength) {
console.log(dnsPacket.streamDecode(response))
client.destroy()
}
})
client.on('close', function () {
console.log('Connection closed')
})