test.lua

--[[
  TODO: Decrypt incoming MSG part from modem (to prevent people executing commands sticking in someone elses name)
  TODO: Add commands for checking permissions (Doors will need to check user permissions)
  TODO: Add commands for adding/removing users/roles/permissions
  TODO: Add commands to enable/disable security on all doors (when disabled, door will open for anyone)
]]--

local computer = require('computer')
local shell = require('shell')
local filesys = require('filesystem')
local term = require('term')
local event = require('event')
local component = require('component')
local modem = component.modem
local gpu = component.gpu

local utils = require('SecurityUtils')

local cRed = 0xFF0000
local cGreen = 0x00FF00
local cWhite = 0xFFFFFF

local permsFile = 'data/permissions.dat'
local rolesFile = 'data/roles.dat'
local usersFile = 'data/users.dat'

local port = 199

if not filesys.exists('data') then
  shell.execute('mkdir data')
end

term.clear()
print("Security server")
print("---------------------------------------------------------------------------")

local permissions = utils.loadTable(permsFile) or {}
local roles = utils.loadTable(rolesFile) or {}
local users = utils.loadTable(usersFile) or {}

function getUser(userName)
  for _, user in pairs(users) do
    if user.name == userName then
      return user
    end
  end

  return nil, "User does not exist!"
end

function getRole(roleName)
  for _, role in pairs(roles) do
    if role.name == roleName then
      return role
    end
  end

  return nil, "Role does not exist!"
end

function hasRole(user, roleName)
  if user and type(user) == "string" then
    user, err = getUser(user)
  end

  if user and user.roles then
    for _, name in ipairs(user.roles) do
      if name == roleName then
        return true
      end
    end
  end

  return false
end

function roleHasPermission(role, permissionName)
  if role and type(role) == "string" then
    role, err = getRole(role)
  end

  if role and role.permissions then
    for _, name in ipairs(role.permissions) do
      if name == permissionName then
        return true
      end
    end
  end

  return false
end

function hasPermission(user, permissionName)
  if user and type(user) == "string" then
    user, err = getUser(user)
  end

  if hasRole(user, 'admin') then
    return true -- Admins access everything regardless
  end

  if user and user.permissions then
    for _, name in ipairs(user.permissions) do
      if name == permissionName then
        return true
      end
    end
  end

  if user and user.roles then
    for _, name in ipairs(user.roles) do
      if roleHasPermission(name, permissionName) then
        return true
      end
    end
  end

  return false
end

function split(str, delimiter)
  local parts = {}

  for bit in (str..delimiter):gmatch("([^"..delimiter.."]*)"..delimiter) do
    table.insert(parts, bit)
  end

  return parts
end

if modem.isOpen(port) then
  term.write('Attempting networking connection...CONNECTED\n')
end

while true do
  if not modem.isOpen(port) then
    term.write('Attempting networking connection...')
    while not modem.isOpen(port) do
      modem.open(port)
      os.sleep(0.01)
    end
    term.write('CONNECTED\n')
  end

  local _, _, from, port, _, command, msg = event.pull('modem_message')

  if msg then
    local data = split(msg, ';')

    if #data > 0 then
      local userName = data[1]
      data[1] = nil

      term.write(from..":"..port..": "..command..' ['..msg..']\n')

      if command == "reboot" then
        if hasRole(userName, 'admin') then
          computer.shutdown(true)
        else
          gpu.setForeground(cRed)
          term.write('Reboot denied for '..userName)
          gpu.setForeground(cWhite)
        end
      end

    end
  end

  os.sleep(0.01)
end

if modem.isOpen(port) then
  modem.close(port)
end