WSL 2 TPC Network Forwarding

README.md

Pulled from microsoft/WSL#4150 - microsoft/WSL#4150 (comment).

WSL 2 TPC NETWORK FORWARDING

Introduction

With the introduction of WSL 2 Beta, Microsoft has made changes to the system architecture. The changes include changing from the default bridged network adapter to a hyper-v virtual network adapter. The implementation was not completed during the launch of the beta program. This makes accessing of network resources under WSL 2 complex. The work around is to forward the TCP ports of WSL 2 services to the host OS. The virtual adapter on WSL 2 machine changes it's ip address during reboot which makes it tough to implement a run once solution. Also a side note, windows firewall will block the redirected port.

The work around is to use a script that does :

1. Get Ip Address of WSL 2 machine
2. Remove previous port forwarding rules
3. Add port Forwarding rules
4. Remove previously added firewall rules
5. Add new Firewall Rules

Configuration

The script must be run at login ,under highest privileges to work, and Powershell must be allowed to run external sources.

PowerShell Configuration

Enable power shell to run external scripts, run the command below in power shell with administrative privileges.

How To: Go to search, search for task scheduler. In the actions menu on the right, click on create task. Enter Name, go to triggers tab. Create a new trigger, with a begin task as you login, set delay to 10s. Go to the actions and add the script. If you are using Laptop, go to settings and enable run on power.

Finally: I am no expert at security nor scripting and technically new to the windows OS.

Update The update adds the feature to remove unwanted firewall rules. Here is the script.

$remoteport = bash.exe -c "ifconfig eth0 | grep 'inet '"
$found = $remoteport -match '\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}';

if( $found ){
  $remoteport = $matches[0];
} else{
  echo "The Script Exited, the ip address of WSL 2 cannot be found";
  exit;
}

#[Ports]

#All the ports you want to forward separated by coma
$ports=@(80,443,10000,3000,5000);


#[Static ip]
#You can change the addr to your ip config to listen to a specific address
$addr='0.0.0.0';
$ports_a = $ports -join ",";


#Remove Firewall Exception Rules
iex "Remove-NetFireWallRule -DisplayName 'WSL 2 Firewall Unlock' ";

#adding Exception Rules for inbound and outbound Rules
iex "New-NetFireWallRule -DisplayName 'WSL 2 Firewall Unlock' -Direction Outbound -LocalPort $ports_a -Action Allow -Protocol TCP";
iex "New-NetFireWallRule -DisplayName 'WSL 2 Firewall Unlock' -Direction Inbound -LocalPort $ports_a -Action Allow -Protocol TCP";

for( $i = 0; $i -lt $ports.length; $i++ ){
  $port = $ports[$i];
  iex "netsh interface portproxy delete v4tov4 listenport=$port listenaddress=$addr";
  iex "netsh interface portproxy add v4tov4 listenport=$port listenaddress=$addr connectport=$port connectaddress=$remoteport";
}

wsl-forward.ps1

$remoteport = bash.exe -c "ifconfig eth0 | grep 'inet '"
$found = $remoteport -match '\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}';

if( $found ){
  $remoteport = $matches[0];
} else{
  echo "The Script Exited, the ip address of WSL 2 cannot be found";
  exit;
}

#[Ports]

#All the ports you want to forward separated by coma
$ports=@(80,443,10000,3000,5000);


#[Static ip]
#You can change the addr to your ip config to listen to a specific address
$addr='0.0.0.0';
$ports_a = $ports -join ",";


#Remove Firewall Exception Rules
iex "Remove-NetFireWallRule -DisplayName 'WSL 2 Firewall Unlock' ";

#adding Exception Rules for inbound and outbound Rules
iex "New-NetFireWallRule -DisplayName 'WSL 2 Firewall Unlock' -Direction Outbound -LocalPort $ports_a -Action Allow -Protocol TCP";
iex "New-NetFireWallRule -DisplayName 'WSL 2 Firewall Unlock' -Direction Inbound -LocalPort $ports_a -Action Allow -Protocol TCP";

for( $i = 0; $i -lt $ports.length; $i++ ){
  $port = $ports[$i];
  iex "netsh interface portproxy delete v4tov4 listenport=$port listenaddress=$addr";
  iex "netsh interface portproxy add v4tov4 listenport=$port listenaddress=$addr connectport=$port connectaddress=$remoteport";
}