Role Name

An ansible role to easily deploy new systemd services. Used for Shellphish's iCTF competition, but can be as generic as wanted, any PRs are welcome.

Requirements

This role registers systemd services, so systemd must be installed and running.

Role Variables

The variable structure closely mimics systemd's Unit files to be self explanatory. Some reasonable defaults are set to reduce the amount of boilerplate code.

An up-to-date example using all currently supported variables should always be found in tests/full.yml, but it looks like this:

    - name: install a random file dumper as a systemd service
      include_role:
        name: register_systemd_service
      vars:

        Name: r4nD0m
        Enabled: true

        Unit:
          Description: Crazy amounts of randomness
          After:
            - network.target
            - multi-user.target
          Requires:
            - network.target
            - multi-user.target
          AssertPathExists:
            - # to get rid of all other asserts
            - /
            - /tmp
            - /dev/urandom
            - /bin/bash

        Service:
          WorkingDirectory: /tmp
          Environment:
            ASDF: "abc"
            DEFG: "def"
          Restart: always
          User: root
          ExecStart: "/bin/bash -c 'while true; do head -n 3 /dev/urandom | tee /tmp/r4Nd0m; echo $ASDF >> /tmp/r4Nd0m; sleep 10; done'"

        Install:
          WantedBy: multi-user.target

As you can see most variables directly match the corresponding structure in the Unit files.

Dependencies

None

Example Playbook

A minimal example of a service can be created with the following playbook. A service requires at least a name, a working directory and a command to

  tasks:
    - name: install a random file dumper as a systemd service
      include_role:
        name: register_systemd_service
      vars:
        Name: r4nD0m
        Service:
          WorkingDirectory: /tmp
          ExecStart: "/bin/bash -c 'while true; do head -n 3 /dev/urandom | tee /tmp/r4Nd0m; sleep 10; done'"

This creates the following service unit file in /etc/systemd/system/r4nD0m.service:

# Service file created by register_systemd_service for Service r4nD0m

[Unit]
Description = r4nD0m
After = network.target

AssertPathExists = /tmp

[Service]
WorkingDirectory= /tmp

ExecStart=/bin/bash -c 'while true; do head -n 3 /dev/urandom | tee /tmp/r4Nd0m; sleep 10; done'
Restart= always

[Install]

License

MIT