SOCKS server in Kubernetes

README.md

SOCKS server in Kubernetes for debug/testing purpose

The reason for this is basically the following:

I need to go out for the public IP of my Kubernetes cluster to debug an external website and I want to do it from my local machine (using the browser in fact). Therefore, I will be able to navigate from my local using crossing traffic through a pod, using Openssh-Server as SOCKSV5 Server.

REMEMBER: DEBUGING OR TESTING PURPOSE!!!

Credits

The official image of this SSH server is from linuxserver.io

Steps

Build your own image. The Dockerfile has a slight change from the official image. Enable TCP forward.

FROM docker.io/linuxserver/openssh-server:latest
# latest is not a good practice, but this is for testing purpose

RUN sed -i 's/AllowTcpForwarding no/AllowTcpForwarding yes/g' /etc/ssh/sshd_config

Build the image using the script

Inside the script build.sh change the docker hub username/repository (or custom repository).

#!/usr/bin/env bash

# I'm using buildx since I'm using Kubernetes nodes with amd64 but my personal laptop it's arm64
docker buildx build --platform linux/amd64 \
--no-cache \
--pull \
-t docker.io/containerscrew/socks-k8s:latest .

docker push docker.io/containerscrew/socks-k8s:latest

Change containerscrew/socks-k8s and put your own user.

Execute the script:

./build.sh

Deploy the pod in your cluster

kubectl apply -f pod.yml

Take a look in the pod.yml and change what you need

Port forward from your pod to your local

kubectl port-forward pod/socks-pod 2222:2222 -n default

SOCKS tunnel using ssh in your local machine

ssh -D8080 admin@localhost -p 2222

Password is admin (the password can be changed in pod.yml)

Also you can execute the following command to run in background

ssh -qNfC -D8080 admin@localhost -p 2222

Execute your first connection tunneled by the socks proxy

First:

curl ifconfig.me

Then:

curl -x socks5h://127.0.0.1:8080 ifconfig.me

Browser

To be able to tunnel connections in your browser, you need to install a plugin such as Socks5 Proxy. Configure it to make requests to 127.0.0.1:8080.

build.sh

#!/usr/bin/env bash

# I'm using buildx since I'm using Kubernetes nodes with amd64 but my personal laptop it's arm64
docker buildx build --platform linux/amd64 \
  --no-cache \
  --pull \
  -t docker.io/containerscrew/socks-k8s:latest .

docker push docker.io/containerscrew/socks-k8s:latest

Dockerfile

FROM docker.io/linuxserver/openssh-server:latest
# latest is not a good practice, but this is for testing purpose

RUN sed -i 's/AllowTcpForwarding no/AllowTcpForwarding yes/g' /etc/ssh/sshd_config

pod.yml

apiVersion: v1
kind: Pod
metadata:
  name: socks-pod
  namespace: default
spec:
  terminationGracePeriodSeconds: 5
  containers:
    - image: docker.io/containerscrew/socks-k8s:latest
      imagePullPolicy: Always
      name: socks-pod
      resources:
        limits:
          cpu: 100m
          memory: 512Mi
        requests:
          cpu: 50m
          memory: 128Mi
      env:
        - name: PUID
          value: "1000"
        - name: PGID
          value: "1000"
        - name: TZ
          value: "Etc/UTC"
        - name: USER_PASSWORD
          value: "admin"
        - name: USER_NAME
          value: "admin"
        - name: PASSWORD_ACCESS
          value: "true"
        - name: SUDO_ACCESS
          value: "false"
      ports:
        - containerPort: 2222
  restartPolicy: Never
#  nodeSelector:
#    Nodegroup: test
#  tolerations:
#    - key: "dedicated"
#      operator: "Equal"
#      value: "test"
#      effect: "NoSchedule"