cli-transparent-tunnel

Introduction

SSH tunneling is a great method of transporting arbitrary networking data over an encrypted SSH connection. It can be used to add

encryption to legacy applications.
access network servers behind an ssh bastion server
and more ..

To do so, we need to create an SSH tunnel and point the local client to the tunnel's local port.

for examples, running psql command through a ssl tunnel

# open a tunnel in a one terminal 
# make sure 3307 is not in use
>> ssh -N -L 5432:my-bastion-server:5432 -p 22 <>USER>@<IP> 

## run psql command in another terminal 
>> psql -U username -h 127.0.0.1 -P 5432 -p password -f commands.sql

I found it a bit tedious and a bit complicated for scenarios such as CI etc .

ctt allows you to prefix any supported command, the tool will preform all the heavy lifting of creating the tunnel and adjusting the cli with the proper host and port.

>> ctt --tunnel-config psql-us psql -U username -p password -f commands.sql  

psql -h 127.0.0.1 -P 65152 -U username -p password -f commands.sql

How

ctt has 2 config files, one for tunnel configurations, and other for command config

e.g:

cli-config

commands-configuration:
  redis-cli:
    path: /usr/local/bin/redis-cli
    flags:
      host:
        - -h
      port:
        - -p
      sni:
        - --sni
  psql:
    path: /usr/local/bin/psql
    flags:
      host:
        - --host
        - -h
      port:
        - -p
        - --port
  kubectl:
    path: /usr/local/bin/kubectl
    flags:
      address:
        - --server
        - -s
      sni:
        - --tls-server-name
  oc:
    path: /usr/local/bin/oc
    flags:
      address:
        - --server
        - -s
      sni:
        - --tls-server-name

In theory, ctt should support any cli that allows passing endpoint using a flag.

tunnel-config

configurations:
  redis-cli:
    - ssh-tunnel-server: my-user@eu-bastion:22
      name: redis-eu
      origin-server: redis:6379
  psql:
    - ssh-tunnel-server: my-user@us-bastion:22
      origin-server: postgres:5432
      name: psql-us
  kubectl:
    - ssh-tunnel-server: my-user@us-bastion:22
      origin-server: k8s:443
      name: k8s-us
  oc:
    - ssh-tunnel-server: my-user@us-bastion:22
      origin-server: k8s:443
      name: oc-conf
ssh-config:
  key-path: ~/ssh/id_rsa

Installation

>> brew tap odedpriva/ctt
>> brew install ctt

Usage

NAME:
   ctt - make a command run through an ssh tunnel

USAGE:
   ctt [global options] command [command options] [arguments...]

COMMANDS:
   setup
   tunnel
   help, h  Shows a list of commands or help for one command

GLOBAL OPTIONS:
   --debug     debug mode (default: false)
   --help, -h  show help (default: false)

tunnel

NAME:
   ctt tunnel

USAGE:
   ctt tunnel [command options] command-to-tunnel [command-to-tunnel-options]

OPTIONS:
   --tunnel-config value  tunnel config name

Setup

TODO ..