permission.rb

require 'net/ssh'
require 'optparse'

options = {}

OptionParser.new do |opts|
  opts.banner = "Usage: ruby permission.rb [-h some-host-option -a lock -u garion]"

  %i{host user action}.each do |option|
    opts.on("-#{option[0]}VALUE", "--#{option}=VALUE") do |value|
      options[option] = value
    end
  end
end.parse!

# get arguments from command line
# decide what to do with them
# and verify they are legit commands

hostname = options[:host]
lock = options[:action]
user = options[:user]

case lock
  when "lock"
     cmd = "sudo chsh -s /usr/bin/false #{user}"
     locker(hostname, cmd)
  when "unlock"
     cmd = "sudo chsh -s /bin/bash #{user}"
     locker(hostname, cmd)
 else quit
 end

def locker(host, cmd)
  begin
    ssh = Net::SSH.start(host)
    res = ssh.exec!(cmd)
    ssh.close
    puts res
  rescue
    puts "Unable to connect to #{@hostname}!"
  end
end