Tarnchat v1 Mirror

--Encryption program by PixelToast! Thanks!
local function zfill(N)
    N=string.format("%X",N)
    Zs=""
    if #N==1 then
        Zs="0"
    end
    return Zs..N
end

local function serializeImpl(t)
    local sType = type(t)
    if sType == "table" then
        local lstcnt=0
        for k,v in pairs(t) do
            lstcnt = lstcnt + 1
        end
        local result = "{"
        local aset=1
        for k,v in pairs(t) do
            if k==aset then
                result = result..serializeImpl(v)..","
                aset=aset+1
            else
                result = result..("["..serializeImpl(k).."]="..serializeImpl(v)..",")
            end
        end
        result = result.."}"
        return result
    elseif sType == "string" then
        return string.format("%q",t)
    elseif sType == "number" or sType == "boolean" or sType == "nil" then
        return tostring(t)
    elseif sType == "function" then
        local status,data=pcall(string.dump,t)
        if status then
            return 'func('..string.format("%q",data)..')'
        else
            error()
        end
    else
        error()
    end
end

local function split(T,func)
    if func then
        T=func(T)
    end
    local Out={}
    if type(T)=="table" then
        for k,v in pairs(T) do
            Out[split(k)]=split(v)
        end
    else
        Out=T
    end
    return Out
end

local function serialize( t )
    t=split(t)
    return serializeImpl( t, tTracking )
end

local function unserialize( s )
    local func, e = loadstring( "return "..s, "serialize" )
    local funcs={}
    if not func then
        return e
    end
    setfenv( func, {
        func=function(S)
            local new={}
            funcs[new]=S
            return new
        end,
    })
    return split(func(),function(val)
        if funcs[val] then
            return loadstring(funcs[val])
        else
            return val
        end
    end)
end

local function sure(N,n)
    if (l2-n)<1 then N="0" end
    return N
end

local function splitnum(S)
    Out=""
    for l1=1,#S,2 do
        l2=(#S-l1)+1
        CNum=tonumber("0x"..sure(string.sub(S,l2-1,l2-1),1) .. sure(string.sub(S,l2,l2),0))
        Out=string.char(CNum)..Out
    end
    return Out
end

local function wrap(N)
    return N-(math.floor(N/256)*256)
end

function checksum(S,num)
    local sum=0
    for char in string.gmatch(S,".") do
        for l1=1,(num or 1) do
            math.randomseed(string.byte(char)+sum)
            sum=sum+math.random(0,9999)
        end
    end
    math.randomseed(sum)
    return sum
end

local function genkey(len)
    checksum(encKey)
    local key={}
    local tKeys={}
    for l1=1,len do
        local num=math.random(1,len)
        while tKeys[num] do
            num=math.random(1,len)
        end
        tKeys[num]=true
        key[l1]={num,math.random(0,255)}
    end
    return key
end

function encrypt(data)
    data=serialize(data)
    local chs=checksum(data)
    local key=genkey(#data,encKey)
    local out={}
    local cnt=1
    for char in string.gmatch(data,".") do
        table.insert(out,key[cnt][1],zfill(wrap(string.byte(char)+key[cnt][2])),chars)
        cnt=cnt+1
    end
    return string.sub(serialize({chs,table.concat(out)}),2,-3)
end

function decrypt(data)
    local oData=data
    data=unserialize("{"..data.."}")
    if type(data)~="table" then
        return oData
    end
    local chs=data[1]
    data=data[2]
    local key=genkey((#data)/2,encKey)
    local sKey={}
    for k,v in pairs(key) do
        sKey[v[1]]={k,v[2]}
    end
    local str=splitnum(data)
    local cnt=1
    local out={}
    for char in string.gmatch(str,".") do
        table.insert(out,sKey[cnt][1],string.char(wrap(string.byte(char)-sKey[cnt][2])))
        cnt=cnt+1
    end
    out=table.concat(out)
    if checksum(out or "")==chs then
        return unserialize(out)
    end
    return oData,out,chs
end



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

print("Enter encryption key:")
write(">")
encKey = tostring(read())

function LR()
local n=1
while true do
local x, y=term.getCursorPos()
term.clearLine()
if n==1 then write(">LEFT<   RIGHT") else write (" LEFT   >RIGHT<") end
term.setCursorPos(x, y)
a, b=os.pullEventRaw()
while a~="key" do a, b=os.pullEventRaw() end
if b==203 and n==2 then n=1 end
if b==205 and n==1 then n=2 end
if b==28 then print("") break end
end
if n==1 then return true end
if n==2 then return false end
return false
end
local chatTable = { [1] = "Welcome to TarnChat! (/help for commands)" }
local chatLine = 1
local message = ""
local user = "???"
local compID = os.getComputerID()
local toID = ""
local msgMessage = ""
local msgSent = ""

function drawLine()
term.setCursorPos( 1, 17 )
term.clearLine()
for n=1,49 do
io.write("=")
end
term.setCursorPos(1,18)
term.clearLine()
write(username)
write(": ")
write(message)
end
function addChat(str)
if chatLine < 16 then
  table.insert(chatTable, str)
  chatLine = chatLine + 1
else
  for n=1,15 do
   chatTable[n] = chatTable[n+1]
  end
   chatTable[16] = str
  end
end
function quit()
os.exit()
end
function showChat()
term.setCursorPos( 1, 1 )
for n=1,chatLine do
  term.clearLine()
  print(chatTable[n])
end
end
print("Is your modem on the Left or the Right?")
term.setCursorPos(1,18)
if LR() == true then
rednet.open("left")
else
rednet.open("right")
end
term.clear()
repeat
term.setCursorPos(1,1)
print("Enter a username for yourself.")
term.setCursorPos(1,18)
user = read()
if string.len(user) > 9 then
term.setCursorPos(1,2)
print("Name too long! 9 character maximum.")
term.setCursorPos(1,18)
elseif string.len(user) > 0 then
write("Your username is ")
write(user)
print("")
print("Entering Chat...")
username = user
end
until string.len(user) ~=0
sleep(2.0)
term.clear()
drawLine()
rednet.broadcast(encrypt(""))
rednet.broadcast(encrypt(username .. " enters the room!"))
repeat

term.setCursorPos(1,1)
write(chatTable[chatLine] or "")
drawLine()
showChat()
term.setCursorPos((3 + string.len(username) + string.len(message)),18)
term.setCursorBlink( true )

event, param = os.pullEventRaw()
if event == "key" then
  if param == 28 then
   if string.sub(message,1,1) == "/" then
        if string.sub(message,1,6) == "/name " then
         if string.len(message) > 6 then
          if string.len(message) < 16 then
           user = username
           username = string.sub(message,7,string.len(message))
           message = "User '" .. user .. "' is now called '" .. username .. "'!"
           rednet.broadcast(encrypt(""))
           rednet.broadcast(encrypt(message))
           addChat(message)
           message = ""
           drawLine()
          else
           addChat("<SYS> Name too long! Maximum 9 characters.")
           message = ""
          end
         end
        elseif string.sub(message,1,4) == "/me " then
         local meMessage = string.sub(message,4,string.len(message))
         message = "*" .. username .. meMessage
         rednet.broadcast(encrypt(""))
         rednet.broadcast(encrypt(message))
         addChat(message)
         message = ""
         drawLine()
        elseif string.sub(message,1,5) == "/list" then
         rednet.broadcast(encrypt(""))
         rednet.broadcast(encrypt(message))
         message = ""
        elseif string.sub(message,1,5) == "/exit" then
         addChat("<SYS> Goodbye!")
         rednet.broadcast(encrypt(""))
         rednet.broadcast(encrypt("User '" .. username .. "' exits the room."))
         sleep(1.0)
         term.clear()
         term.setCursorPos(1,1)
         break
        elseif string.sub(message,1,5) == "/quit" then
         addChat("<SYS> Goodbye!")
         rednet.broadcast(encrypt(""))
         rednet.broadcast(encrypt("User '" .. username .. "' exits the room."))
         sleep(1.0)
         term.clear()
         term.setCursorPos(1,1)
         break
        elseif string.sub(message,1,5) == "/help" then
         addChat("/help - lists programs")
         addChat("/name <name> - changes username")
         addChat("/list - lists connected users, and console IDs")
         addChat("/me - used as emote")
         addChat("/clear - clears the screen")
         addChat("/msg <ID> <message> - sends a private message")
         addChat("/exit - exits the program")
         message = ""
        elseif string.sub(message,1,5) == "/msg " then
         if string.len(message) > 5 then
          if string.sub(message,7,7) == " " then
           toID = string.sub(message,6,6)
           msgMessage = string.sub(message,8,string.len(message))
           addChat("You whisper to #" .. toID .. ": " .. msgMessage)
           message = username .. " whispers to you: " .. msgMessage
           toID = tonumber(toID)
           rednet.send(toID,encrypt(""))
           rednet.send(toID,encrypt(message))
           message = ""
          elseif string.sub(message, 8,8) == " " then
           toID = string.sub(message,6,7)
           msgMessage = string.sub(message,9,string.len(message))
           addChat("You whisper to #" .. toID .. ": " .. msgMessage)
           message = username .. " whispers to you: " .. msgMessage
           toID = tonumber(toID)
           rednet.send(toID,encrypt(""))
           rednet.send(toID,encrypt(message))
           message = ""
          elseif string.sub(message, 9,9) == " " then
           toID = string.sub(message,6,8)
           msgMessage = string.sub(message,10,string.len(message))
           addChat("You whisper to #" .. toID .. ": " .. msgMessage)
           message = username .. " whispers to you: " .. msgMessage
           toID = tonumber(toID)
           rednet.send(toID,encrypt(""))
           rednet.send(toID,encrypt(message))
           message = ""
          elseif string.sub(message,10,10) == " " then
           toID = string.sub(message,6,9)
           msgMessage = string.sub(message,11,string.len(message))
           addChat("You whisper to #" .. toID .. ": " .. msgMessage)
           message = username .. " whispers to you: " .. msgMessage
           toID = tonumber(toID)
           rednet.send(toID,encrypt(""))
           rednet.send(toID,encrypt(message))
           message = ""
          end
         end
        elseif string.sub(message,1,3) == "/m " then
         if string.len(message) > 3 then
          if string.sub(message,5,5) == " " then
           toID = string.sub(message,4,4)
           msgMessage = string.sub(message,6,string.len(message))
           addChat("You whisper to #" .. toID .. ": " .. msgMessage)
           message = username .. " whispers to you: " .. msgMessage
           toID = tonumber(toID)
           rednet.send(toID,encrypt(""))
           rednet.send(toID,encrypt(message))
           message = ""
          elseif string.sub(message, 6,6) == " " then
           toID = string.sub(message,4,5)
           msgMessage = string.sub(message,7,string.len(message))
           addChat("You whisper to #" .. toID .. ": " .. msgMessage)
           message = username .. " whispers to you: " .. msgMessage
           toID = tonumber(toID)
           rednet.send(toID,encrypt(""))
           rednet.send(toID,encrypt(message))
           message = ""
          elseif string.sub(message, 7,7) == " " then
           toID = string.sub(message,4,6)
           msgMessage = string.sub(message,8,string.len(message))
           addChat("You whisper to #" .. toID .. ": " .. msgMessage)
           message = username .. " whispers to you: " .. msgMessage
           toID = tonumber(toID)
           rednet.send(toID,encrypt(""))
           rednet.send(toID,encrypt(message))
           message = ""
          elseif string.sub(message,8,8) == " " then
           toID = string.sub(message,4,7)
           msgMessage = string.sub(message,9,string.len(message))
           addChat("You whisper to #" .. toID .. ": " .. msgMessage)
           message = username .. " whispers to you: " .. msgMessage
           toID = tonumber(toID)
           rednet.send(toID,encrypt(""))
           rednet.send(toID,encrypt(message))
           message = ""
          end
         end
        elseif string.sub(message,1,6) == "/clear" then
         term.clear()
         for n=1,16 do
          addChat(" ")
         end
         chatTable = {}
         chatLine = 1
         message = ""
        else
         message = ""
        end
   else
        if string.len(message) > 0 then
          username = tostring(username)
          message = tostring(message)
          message = "<" .. username .. "> " .. message
          rednet.broadcast(encrypt(""))
          rednet.broadcast(encrypt(message))
          addChat(message)
          message = ""
          drawLine()
        end
   end
  elseif param == 14 then
   message = string.sub(message,1,string.len(message)-1)
   drawLine()
  end
end

if event == "char" then
  if string.len(message) < 40 then
        message = message .. param
  end
  drawLine()
end

if event == "rednet_message" then
  id, incoming = rednet.receive(0.5)
  incoming = decrypt(incoming)

  if incoming == "/list" then
   rednet.send(id,encrypt(""))
   rednet.send(id,encrypt("User '" .. username .. "' is connected at terminal #" .. compID))
  else
   addChat(incoming)
  end
end

until message == "override"