Bypass OpenVPN connection

bypass ovpn.md

Background Story

Since the .ovpn have a setting with

redirect-gateway def1 bypass-dhcp
dhcp-option DOMAIN-ROUTE . 

Therefore, your PC network route will all go through the VPN. Which make the connection failed in local
Cannot surfing the web 🚫🚫🚫🚫

Solution?

Note

This workaround not modify any content inside the .ovpn file or route table

The solution is very simple, use a docker container to run the ovpn
VPN setting will only apply inside the docker container environment
Expose the port & ip to let local network to access

Full Architechture

[ Host Machine (Your PC) ] ───> Physical NIC (Wi-Fi/Ethernet) ───> Normal Local Internet (Fast & Untouched)
       │
       ├───> [ Proxifier (Host) ] ───> Intercepts {your target device IP} ───> Forwards to localhost:{your fav port}
       │                                                                   │
       └─> [ Docker Engine (WSL2) ] ───────────────────────────────────────┘
                 │
                 └─> [ Shared Network Space ]
                           │
                           ├──> [ Service 2: Gost (SOCKS5 Server) ] ───> Listens on port {your fav port}
                           │                                                   │
                           └──> [ Service 1: OpenVPN Client Container ] ───────┘
                                     │
                                     ├──> Connects to {provided VPN domain}
                                     └──> Highjacks CONTAINER-ONLY routes & DNS

Prerequest

• Proxifier
• Docker Desktop
• Any Auth App (e.g. Google Auth, Authenticator>

  if require 2FA access

Application Setup Guide

Proxifier SetUp

1. Create Proxy Server

Go to Menu, Open "Profile" > "Proxy Servers..."
"Add" a new server
Address: 127.0.0.1 | port: {your fav port} | Protocol: SOCKS VERSION 5
OK to Save

2. Create Proxification Rules

Go to Menu, Open "Profile" > "Proxification Rules..."
"Add" a new rule
Name: {your fav name} | Target host: {your target device IP} | Action: {the proxy server create in part 1}
OK to Save

Docker SetUp

File Preparation

File Structure

Create the below structure in any directory of your PC

vpn-proxy/
├── compose.yml
└── vpn/
    ├── {provided}.ovpn
    ├── credentials.txt
    └── private_key_pwd.txt

Some value in template should change on your own

{port} — the port should be same as proxifier setting
{provided}.ovpn — the .ovpn file, use your own name

1. Create compose.yml

Download the compose.yml
Change the {port} and {provided}

Open Vpn Ref

2. Create credentials.txt

Download or create credentials.txt
Fill in {user name} {password}

3. Create private_key_pwd.txt

Download or create password.txt
Fill in {private key password}

Docker Image build

1. Open & Start Docker Desktop
2. Goto the compose.yml directory.
3. open cmd/terminal run docker compose up -d

Connection Guide

Note

this part is start from the init state, no "already in use" application or process

Start up & Prepare application

1. Open Docker Destop (MUST)
2. Open Proxifier (MUST)
3. Prepare your auth tools

Docker kick start & vpn service

MUST already open the Docker Desktop

1. Goto the compose.yml location
2. run docker compose start
3. run docker attach openvpn-client
4. Fill in the 6-digit Auth code & Press Enter (if any)

   OpenVPN often doesn't automatically re-prompt or flush the stdout to show the 2FA Enter Authenticator Code hint when a new terminal attaches, leaving you staring at a blank, frozen screen.

   1. Even if the screen is blank or stuck on old logs, just type your 2FA code and hit Enter.
   2. OpenVPN will often accept the input anyway and proceed with the connection.
   3. Once connected, safely detach by pressing Ctrl + P then Ctrl + Q.

   if you input the wrong 2FA code, please detach first and do the following command
   docker compose restart
   docker attach openvpn-client
   

Start Remote Connection

1. Open your remote desktop tools, fill in the {target device IP}

compose.yml

# template only
# {port} , {provided} must be fill in

version: '3.8'

services:
  openvpn-client:
    container_name: openvpn-client
    image: my-openvpn-client:local
    build:
      context: .
      dockerfile_inline: |
        FROM alpine:latest
        RUN apk add --no-cache openvpn
        WORKDIR /vpn
    entrypoint: ["openvpn"]
    command: ["--config", "/vpn/{provided}.ovpn", "--auth-user-pass", "/vpn/credentials.txt", "--askpass", "/vpn/private_key_pwd.txt"]
    cap_add:
      - NET_ADMIN
    devices:
      - /dev/net/tun:/dev/net/tun
    volumes:
      - ./vpn:/vpn
    stdin_open: true
    tty: true
    ports:
      - "{port}:{port}"
    restart: unless-stopped

  gost:
    image: ginuerzh/gost:latest
    container_name: gost-proxy
    network_mode: "container:openvpn-client"
    command: "-L socks5://:{port}"
    depends_on:
      - openvpn-client
    restart: unless-stopped

credentials.txt

{user name}
{password}

private_key_pwd.txt

{private key password}