gont

README

Gont - A Go network testing toolkit

Gont is a package to creat realistic virtual network, running real kernel, switch and application code, on a single machine (VM, cloud or native).

Gont is heavily inspired by Mininet. It allows the user to build virtual network topologies using Go code. Under to hood the network is then constructed using Linux virtual bridges and network namespaces.

Features

• L3 Routers
• L2 Switches
• L3 NAT Routers
• L3 Host NAT (to host network)
• Hostname resolution (using /etc/hosts)
• Support for multiple simultaneous and isolated networks
• Ideal for golang unit tests
• Can run in workflows powered by GitHub's runners
• Lean code thanks to functional options

Examples

Have a look at the unit tests for usage examples:

• Simple
• Run
• NAT
• Switch
• Links

Prerequisites

• iptables (for NAT)
• ping (for testing)
• traceroute (for testing)

Roadmap

• NAT
  • Use netlink socket instead of iptables tool for configuring NAT
  • Use netlink socket instead of ipset tool for configuring NAT
• Integrate go imlementations of ping and traceroute tools
• More tests
• Fix host NAT
• Add support for netem and tbf qdiscs on Links
• Add separate examples directory
• Topology factories
• Full IPv6 support

Architecture

classDiagram
    direction RL

    class Network {
        Nodes []Node
        Links []Link
    }

    class Link {
        Left Endpoint
        Right Endpoint
    }

    class Endpoint {
    }

    class Port {
        Name string
        Node Node
    }

    class Interface {
        Addresses []net.IPNet
    }

    class Namespace {
        NsFd int
        Run()
    }

    class Node {
        Name string
    }

    class Host {
        Interfaces []Interface
        AddInterface()
    }

    class Switch {
        Ports []Port
        AddPort()
    }

    class Router {
        AddRoute()
    }

    class NAT {

    }
            
    Node *-- Namespace
    Host *-- Node
    Router *-- Host
    NAT *-- Router
    Switch *-- Node

    Port *-- Endpoint
    Interface *-- Port

    Port "1" o-- "1" Node

    Host "1" o-- "*" Interface
    Switch "1" o-- "*" Port

    Link "1" o-- "2" Endpoint

    Network "1" o-- "*" Link
    Network "1" o-- "*" Node

Credits

• Steffen Vogel (@stv0g)

Funding acknowledment

The development of Gont has been supported by the [ERIGrid 2.0] project of the H2020 Programme under Grant Agreement No. 870620