kumo_v1.rb

require 'slack-ruby-client'
require 'net/http'
require 'logger'

# random logging for later analysis
logger = Logger.new('bot.log')

# public ip address for connecting to
PUBLIC_IP = Net::HTTP.get(URI "https://api.ipify.org").strip

# clear old keys
`echo "" > /game_keys` 

User = Struct.new(:id, :logger) do
  def has_ssh_key?
    logger.info("Checking if " + id + " has an SSH key")
    if File.file?(id)
      logger.info(id + " had an SSH key")
      return true
    else
      logger.info(id + " did not have an SSH key")
      return false
    end
  end
  
  def generate_ssh_key
    logger.info("Generated SSH key for " + id)
    `ssh-keygen -f #{id} -t rsa -b 4096 -N ''`
    open('/game_keys', 'a') { |f| 
	f.puts "command=\"sudo docker run -it --rm ubuntu\" #{public_ssh_key.strip}"
    }
    return true
  end

  def private_ssh_key 
    unless has_ssh_key?
      generate_ssh_key
    end
    logger.info("Reading private ssh key for " + id)
    IO.binread(id)
  end

  def public_ssh_key
    unless has_ssh_key?
      generate_ssh_key
    end
    logger.info("Reading public ssh key for " + id)
    IO.binread(id + ".pub")
  end
end

class GameServer
  def initialize(logger)
    @logger = logger
    @users = {}
  end

  def logger
    @logger
  end

  def users
    @users
  end

  def add_user(id)
    if users[id]
      logger.info("Unable to add " + id + "to the game")
      return false
    else
      @users[id] = User.new(id, @logger)
      logger.info(id + " was added to the game")
    end
  end
end

game_server = GameServer.new(logger)

Slack.configure do |config|
  logger.info("configuring slack bot")
  config.token = 'YOUR-TOKEN-GOES-HERE-LOL'
end

client = Slack::RealTime::Client.new

trap("SIGINT") { logger.warn("Exiting application!"); puts "Exiting!" ; exit; }
        
HELP = "`join` : join the enviroment and get your private ssh key.\n" + "`joined?` : check if you've already joined\n" + "`ip address` : get the public facing ip address of the server to connect to.\n" + "`ssh` : show your private ssh key and an example how to login again.\n" + "`help` : show this help menu again.\n" 

client.on :message do |data|
  if client.ims[data.channel]
    case data.text
    when /join\b/i then
      unless game_server.users[data.user]
        logger.info("Added a new user " + data.user)
        game_server.add_user(data.user)
        logger.info("Delivering first SSH key upon joinging to " + data.user)
        client.message channel: data.channel, text: ":dragon: *Welcome to the Kumo Dōjō!* 雲道場 -- Cloud-based security competition practice enviroment.\n> Use the following :key: *ssh private key* to login to the enviroment:\n ```#{game_server.users[data.user].private_ssh_key}```\n" + "Use your `kumo` public ssh key: `ssh ubuntu@#{PUBLIC_IP} -i kumo`"
      else
        logger.info(data.user + " tried to rejoin the game")
        client.message channel: data.channel, text: "*Whoa!* Looks like you've already told me to `join` the dojo. Maybe you're trying to `ssh` into the dojo?" 
      end
    when /joined?\b/i then
	if game_server.users[data.user]
          client.message channel: data.channel, text: "Yup! You've already joined the enviroment." 
	else
          client.message channel: data.channel, text: "You haven't tried to `join` the enviroment yet." 
	end
    when /ip address/i then
      client.message channel: data.channel, text: "The public ip address you can connect to is `#{PUBLIC_IP}`" 
    when /ssh/ then
      if game_server.users[data.user]
        logger.info("Delivering SSH key to " + data.user)
        client.message channel: data.channel, text: "```#{game_server.users[data.user].private_ssh_key}```" 
        client.message channel: data.channel, text: "Use your `kumo` public key: `ssh ubuntu@#{PUBLIC_IP} -i kumo`"
      else
        logger.info(data.user + " tried to get an ssh key without joining the game")
        client.message channel: data.channel, text: "*Whoa!* Looks like you've haven't tried to `join` the dojo."
      end
    when /help/ then
      client.message channel: data.channel, text: HELP
    else
      client.message channel: data.channel, text: HELP
    end
  else
    # ok
  end
end

client.start!