Docker-setup

Docker-setup is a program that allow configure a container (for networking) via environment variables.

Usage

This program only use environment variables for its configuration:

• ONESHOT: when this environment variable is equal to true, the program will not sleep until a signal (SIGINT or SIGTERM) is received, and not perform cleaning scripts on exit
• NAT4_IFACES is a list of interfaces where MASQUERADE will be enabled
• ROUTES_INIT is a list of routes modifications that will be performed on init
• ROUTES_EXIT is a list of routes modifications that will be performed on exit
• PRE_INIT_HOOK is a command that is run before the init (nat & routes init). The command can takes some arguments from PRE_INIT_HOOK_0, PRE_INIT_HOOK_1, and so on.
• POST_INIT_HOOK is a command that is run after the init (nat & routes init). The command can takes some arguments from POST_INIT_HOOK_0, POST_INIT_HOOK_1, and so on.
• PRE_EXIT_HOOK is a command that is run before the exit (nat & routes cleaning). The command can takes some arguments from PRE_EXIT_HOOK_0, PRE_EXIT_HOOK_1, and so on.
• POST_EXIT_HOOK is a command that is run after the exit (nat & routes cleaning). The command can takes some arguments from POST_EXIT_HOOK_0, POST_EXIT_HOOK_1, and so on.

Example

In Docker Compose:

volumes:
    - "./config_init.sh:/usr/local/bin/config_init.sh:ro"
    - "./config_exit.sh:/usr/local/bin/config_exit.sh:ro"
environment:
    ONESHOT: "false"
    ROUTES_INIT: |-
        - add 10.0.1.0/24 via 10.0.0.2
        - add 10.0.2.0/24 via 10.0.0.3
    ROUTES_EXIT: |-
        - del 10.0.1.0/24
        - del 10.0.2.0/24
    NAT4_IFACES: |-
        - eth0
        - eth1
    PRE_INIT_HOOK: config_init.sh
    PRE_INIT_HOOK_0: "Hello"
    PRE_INIT_HOOK_1: "World"
    PRE_INIT_HOOK_2: "!"
    PRE_EXIT_HOOK: config_exit.sh
    PRE_EXIT_HOOK_0: "Goodbye"

Getting started

Build dependencies

• golang

Runtime dependencies

• iproute2
• iptables

Build

Run go build

Docker

• The container requires the NET_ADMIN capability;

This can be done in docker-compose.yaml by defining the following for the service:

cap_add:
    - NET_ADMIN

Author

Louis Royer

License

MIT