doorlock2

--theinsekt's doorlock program
--heavily influenced by http://computercraft.info/wiki/Making_a_Password_Protected_Door
--uses sha256-implementation from http://pastebin.com/gsFrNjbt  (GravityScore)

--to install:
--in computercraft:
--do: rm getlock
--do: pastebin get XCG38Zpi getlock
--do: getlock
--finally hold ctrl-r

os.loadAPI("sha256")

function hash(msg)
 return sha256.sha256(msg)
end

local passPath="password"
local adminPath="adminpass"
local sidePath="side"
local doorTime=3
local testing=false





function loadValue(path)
 local succes=true
 if  not fs.exists(path) then
  return nil
 end
 local h=fs.open(path, "r")
 if h==nil then
  return nil
 end
 local value=h.readAll()
 h.close()
 return value
end



function saveValue(value,path)
 if type(value)~="string" then
  error("Error: value must be a string")
 end
 local h = fs.open(path, "w")
 h.write(value)
 h.close()
 return true
end

--function to set to enable or disable ctrl-t
--http://www.computercraft.info/forums2/index.php?/topic/2732-disable-ctrlt/
local pullEventCopy = os.pullEvent
function setCtrlT(value)
 if value then
  os.pullEvent = pullEventCopy
 else
  os.pullEvent = os.pullEventRaw
 end
end



function checkConfiguration()--checkConfiguration()
 return loadValue(passPath)~=nil and loadValue(adminPath)~=nil and loadValue(sidePath)~=nil
end


function loadDoorValues()
 return loadValue(passPath), loadValue(sidePath), loadValue(adminPath)
end

function adminMode()
 print("Admin mode.")
 setCtrlT(true)--enable ctrl-t
 print("Hold ctrl-t for root access.")
 print("Hold ctrl-r to exit")

 --get a password
 print("New door password:")
 local password=read("*")

 -- get a side
 local sides=redstone.getSides()
 local side=nil
 while(true) do
  for k,v in ipairs(sides) do
   print(k,":",v)
  end
  print("New door side (number):")
  side=read("*")
  if not sides[tonumber(side)] then
   print("Invalid side")
  else
   side=sides[tonumber(side)]
   break
  end
 end

--get an admin password
 local adminPass=nil
 while(true) do
  print("New admin password:")
  local adminPass1=read("*")
  print("New admin password again:")
  local adminPass2=read("*")
  if adminPass1~=adminPass2 then
   print("They are not identical")
  else
   adminPass=adminPass1
   break
  end
 end

 print("Saving...")
 saveValue(hash(password),passPath)--hash passwords
 saveValue(side,sidePath)
 saveValue(hash(adminPass),adminPath)--hash passwords


 --sleep(2) --hashing will take time, so don't need sleep
 setCtrlT(false)--disable ctrl-t
end

function clear()
 term.clear()
 term.setCursorPos(1, 1)
end

function printProgramInfo()
 print("theinsekt's lock v2")
 print("to install:")
 print("do: rm getlock")
 print("do: pastebin get XCG38Zpi getlock")
 print("do: getlock")
 print("finally hold ctrl-r")
 print()
end

setCtrlT(false)--disable ctrl-t
clear()
print("booting...")
sleep(1)
while(true) do
 clear()
 if testing then
  print("debug mode, reactivating ctrl-t")
  setCtrlT(true)--enable ctrl-t
 end
 printProgramInfo()
 if not checkConfiguration() then
  adminMode()
 else --is configured so check password
  local password,side,adminPass=loadDoorValues()
  --print(password, ":", side, ":",adminPass)
  print("Restricted mode.")
  print("Password:")
  local input = read("*")
  input=hash(input)--because passwords are stored hashed
  if input==adminPass then --admin
   clear()
   printProgramInfo()
   adminMode()
  elseif input == password then --password
   print("Correct!")
   redstone.setOutput(side, true)
   sleep(doorTime)
   redstone.setOutput(side, false)
  else --fail
   print("Incorrect!")
   sleep(2)
  end
 end

end

setCtrlT(true)--enable ctrl-t