dnstruncate

Documentation

Overview

Package dnstruncate functions as an alternative implementation that handles DNS requests if the remote server doesn't support UDP traffic. This is done by always setting the TC (truncated) bit in the DNS response header; it tells the caller to resend the DNS request using TCP instead of UDP. As a result, no UDP requests are made to the remote server.

This implementation is ported from the go-tun2socks' dnsfallback.NewUDPHandler.

Note that UDP traffic that are not DNS requests are dropped.

To create a network.PacketProxy that handles DNS requests locally:

proxy, err := dnstruncate.NewPacketProxy()
if err != nil {
	// handle error
}

This `proxy` can then be used in, for example, lwip2transport.ConfigureDevice.

Index

• func NewPacketProxy() (network.PacketProxy, error)

Functions

func NewPacketProxy

func NewPacketProxy() (network.PacketProxy, error)

NewPacketProxy creates a new network.PacketProxy that can be used to handle DNS requests if the remote proxy doesn't support UDP traffic. It sets the TC (truncated) bit in the DNS response header to tell the caller to resend the DNS request over TCP.

This network.PacketProxy should only be used if the remote proxy server doesn't support UDP traffic at all. Note that all other non-DNS UDP packets will be dropped by this network.PacketProxy.