grpc-tunnel

grpc-tunnel provides an example implementation for a client, server and target of the grpc-tunnel framework.

app (ssh, gnmi, etc) - target grpctunnel <------> server grpctunnel <----> client grpctunnel with e.g. ssh-client

grpc-tunnel architecture grpc-tunnel design

Features

Server

• act as a registration server for target ID and target Type

Target

• currently a single tunnel per target list but can be extended
• target names are provided as a string for now
• target types are provided as a string for now

client

• connects to a single grpc tunnel server and can be embedded in a proxy command

Installation

install via the following command

sudo curl -sL https://raw.githubusercontent.com/henderiw/grpc-tunnel/master/get.sh | sudo bash

Upgrades are handled using grpctunnel version upgrade

grpctunnel version upgrade

Setup

generate a certificate for the server

server

start the server

grpctunnel server start --cert-file ~/grpctunnel/serverCert.pem --key-file ~/grpctunnel/serverKey.pem -d

target

start the target, which exposes the local service via the target client.

grpctunnel target start -t ~/grpctunnel/target.cfg -d

a configfile is used to handle the configuration

tunnel_server_default: <
    tunnel_server_address: "<ip address or dns hostname>:<port>"
    credentials: <
        tls: <
        >
    >
>
tunnel_target: <
    target: "target1"
    type: "SSH"
    dial_address: "localhost:22"
>
tunnel_target: <
    target: "target2"
    type: "GNMI"
    dial_address: "localhost:57400"
>

client

the client ca be used in conjunction with the ssh client

ssh -o ProxyCommand='grpctunnel client start -s "<ip address or dns hostname>:<port>" -d' <username>@localhost