IPnet: Client

-----------IPnet Client v1.0---------
-----------------API-----------------
--------------by Creator-------------

--Variables--
local secretInt = math.random(100,9999)
local base = nil
local publicPrime = nil
local subRouter = {}
local configuration = {}
local debugOpt = false
local localChannel = 0
local textutilsserialize = textutils.serialize
local textutilsunserialize = textutils.unserialize
local sharedSecret = nil
local myHalfofTheSecret = nil
--Too many variables--

--Functions--
local function clear()
    term.setCursorPos(1,1)
    term.clear()
end

function baseToPowerMod(base,power,modulus)
  --This function was taken from Anavrins' Diffie-Hellman proof of concept
  --Full code here:http://pastebin.com/H3kZHZBA
  local remainder = base
  for i = 1, power-1 do
    remainder = remainder * remainder
    if remainder >= modulus then
      remainder = remainder % modulus
    end
  end
  return remainder
end

local function debugPrint(txt)
    if debugOpt then
        print(txt)
    end
end

local function getModemSide()
    local sides = {"bottom","right","left","front","back","top"}
    local side = {}
    for i,v in pairs(rs.getSides()) do
        if peripheral.isPresent(v) == true and peripheral.getType(v) == "modem" then
            debugPrint("side:")
            debugPrint(v)
            return v
        end
    end
    debugPrint("Got modem side")
    if #side == 0 then return nil end
end

local function getIP()
    local x , y , z = gps.locate()
    ip = {x,y,z,os.getComputerID()}
    debugPrint("Got ip: ")
    debugPrint(ip)
    return textutilsserialize(ip)
end

local function setConfig()
    local configs = {}
    configs = textutilsunserialize(getIP())
    configs[5] = getModemSide()

    local configFile = fs.open("config","w")
    configFile.write(textutilsserialize(configs))
    configFile.close()
    debugPrint("Wrote configs: ")
    debugPrint(configs)
end

local function setUp()
    if fs.exists("config") then
        configFile = fs.open("config","r")
        tempConfigs = textutilsunserialize(configFile.readAll())
        configFile.close()
        debugPrint("File exists")
    else
        setConfig()
        configFile = fs.open("config","r")
        tempConfigs = textutilsunserialize(configFile.readAll())
        configFile.close()
        debugPrint("File does not exist")
    end
    if tempConfigs[5] == nil then
        setConfig()
        configFile = fs.open("config","r")
        tempConfigs = textutilsunserialize(configFile.readAll())
        configFile.close()
    elseif peripheral.isPresent(tempConfigs[5]) == false then
        setConfig()
        configFile = fs.open("config","r")
        tempConfigs = textutilsunserialize(configFile.readAll())
        configFile.close()
    elseif peripheral.isPresent(tempConfigs[5]) == true and peripheral.getType(tempConfigs[5]) ~= "modem" then
        setConfig()
        configFile = fs.open("config","r")
        tempConfigs = textutilsunserialize(configFile.readAll())
        configFile.close()
    end

    if tempConfigs[5] == nil then
        debugPrint("No modem attached")
        error()
    end

    modem = peripheral.wrap(tempConfigs[5])
    local idChannel = 65522
    local msgChannel = 65523
    modem.open(idChannel)
    modem.open(msgChannel)
    debugPrint("Opened channels:")
    debugPrint(idChannel)
    debugPrint(msgChannel)
    configuration = {tempConfigs[1],tempConfigs[2],tempConfigs[3],tempConfigs[4]}
    debugPrint("configuration")
    debugPrint(textutilsserialize(configuration))
end

local function identificationSubRouter()
    local localChannel
    serilaizedConfig = textutilsserialize(configuration)
    local mainRouterNotFound = true
    modem.transmit(65522,10,serilaizedConfig)
    while mainRouterNotFound do
        local event, side, ch1, ch2, msg, distance = os.pullEvent("modem_message")
        if  pcall(textutilsunserialize,msg) then
            if ch2 == 9 then
                subRouter = textutilsunserialize(msg)
                debugPrint("Channel 2 valid")
                mainRouterNotFound = false
                local eventTwo, sideTwo, ch1Two, ch2Two, msgTwo, distanceTwo = os.pullEvent("modem_message")
                while ch2Two ~= 18 do
                    eventTwo, sideTwo, ch1Two, ch2Two, msgTwo, distanceTwo = os.pullEvent("modem_message")
                end
                debugPrint("msg")
                debugPrint(msgTwo)
                local unserializedMsgTwo = textutilsunserialize(msgTwo)
                localChannel = unserializedMsgTwo[2]
                debugPrint("Opened on channel "..localChannel)
                modem.open(65515)
                local tEvent, tSide, tCh1, tCh2, tMsg, tDistance = nil
                while tCh1 ~= 65515 or tCh2 ~= 1 do
                    tEvent, tSide, tCh1, tCh2, tMsg, tDistance = os.pullEvent("modem_message")
                end
                publicPrime = textutilsunserialize(tMsg)[1]
                base = textutilsunserialize(tMsg)[2]
                myHalfofTheSecret = baseToPowerMod(base,secretInt,publicPrime)
                sharedSecret = baseToPowerMod(textutilsunserialize(tMsg)[3],secretInt,publicPrime)
                modem.transmit(65515,2,myHalfofTheSecret)
                print(sharedSecret)
                modem.close(65515)
            elseif ch2 == 11 then
                modem.transmit(65522,12,serilaizedConfig)
                subRouter = textutilsunserialize(msg)
                debugPrint("Channel 2 valid")
                mainRouterNotFound = false
                local eventTwo, sideTwo, ch1Two, ch2Two, msgTwo, distanceTwo = os.pullEvent("modem_message")
                while ch2Two ~= 18 do
                    eventTwo, sideTwo, ch1Two, ch2Two, msgTwo, distanceTwo = os.pullEvent("modem_message")
                end
                debugPrint("msg")
                debugPrint(msgTwo)
                local unserializedMsgTwo = textutilsunserialize(msgTwo)
                localChannel = unserializedMsgTwo[2]
                debugPrint("Opened on channel "..localChannel)
                modem.open(65515)
                local tEvent, tSide, tCh1, tCh2, tMsg, tDistance = nil
                while tCh1 ~= 65515 or tCh2 ~= 1 do
                    tEvent, tSide, tCh1, tCh2, tMsg, tDistance = os.pullEvent("modem_message")
                end
                publicPrime = textutilsunserialize(tMsg)[1]
                base = textutilsunserialize(tMsg)[2]
                myHalfofTheSecret = baseToPowerMod(base,secretInt,publicPrime)
                sharedSecret = baseToPowerMod(textutilsunserialize(tMsg)[3],secretInt,publicPrime)
                modem.transmit(65515,2,myHalfofTheSecret)
                print(sharedSecret)
                modem.close(65515)
            end
        end
    end
    debugPrint("subRouter")
    debugPrint(textutilsserialize(subRouter))
    debugPrint("Local ch")
    debugPrint(localChannel)
    if fs.exists("confTemp") then
        fs.delete("confTemp")
    end
    confTemp = fs.open("confTemp","w")
    confTemp.write(textutilsserialize({configuration[1],configuration[2],configuration[3],configuration[4],subRouter[1],subRouter[2],subRouter[3],subRouter[4],localChannel}))
    confTemp.close()
end

function send(destPc,msg,port)
    local modemSideFile = fs.open("config","r")
    local modemSide = textutilsunserialize(modemSideFile.readAll())
    modemSideFile.close()
    modem = peripheral.wrap(modemSide[5])
    if type(destPc) == "table" then
        if #destPc == 4 then
            local configTempFile = fs.open("confTemp","r")
            local confTemp = textutilsunserialize(configTempFile.readAll())
            configTempFile.close()
            local msgNum = math.random(1,5000)
            modem.transmit(65523,1,textutilsserialize({destPc,{confTemp[1],confTemp[2],confTemp[3],confTemp[4]},{confTemp[5],confTemp[6],confTemp[7],confTemp[8]},{confTemp[1],confTemp[2],confTemp[3],confTemp[4]},msgNum,msg,port}))
        else
            debugPrint("Your destination IP is a table with the following content: x, y, z and ID of the receiver.")
        end
    else
        debugPrint("Your destination IP is a table with the following content: x, y, z and ID of the receiver.")
    end
end

function receive()
    local event, side, ch1, ch2, msg, distance
    local modemSideFile = fs.open("config","r")
    local modemSide = textutilsunserialize(modemSideFile.readAll())
    modemSideFile.close()
    modem = peripheral.wrap(modemSide[5])
    local configTempFile = fs.open("confTemp","r")
    local confTemp = textutilsunserialize(configTempFile.readAll())
    configTempFile.close()
    modem.open(confTemp[9])
    local continueBool = true
    while continueBool == true do
        event, side, ch1, ch2, msg, distance = os.pullEvent("modem_message")
        debugPrint("recieved msg")
        debugPrint(ch1)
        debugPrint(ch2)
        debugPrint(msg)
        debugPrint(textutilsserialize(confTemp))
        pcall(textutilsunserialize,msg)
        if ch1 == confTemp[9] and ch2 == 1 then
            continueBool = false
        end
    end
    modem.close(confTemp[9])
    return msg
end

function toReturn()
    clear()
    setUp()
    identificationSubRouter()
    modem.close(65522)
    modem.close(65523)
    return textutilsserialize(configuration)
end