---
-- This Lua script is designed to run with Iceman/RRG Proxmark3 fork
-- Just copy luxeodump.lua to client/luascripts/
-- and run "script run luxeodump"

-- requirements
local cmds = require('commands')
local getopt = require('getopt')
local utils = require('utils')
local lib14a = require('read14a')
local ansicolors  = require('ansicolors')

copyright = ''
author = '0xdrrb'
version = 'v0.1.0'
desc = [[
This is a script to dump and decrypt the data of a specific type of Mifare laundromat token.
]]
example = [[
    script run luxeodump
]]
usage = [[
script run luxeodump
]]

local PM3_SUCCESS = 0

-- Some shortcuts
local band = bit32.band
local bor = bit32.bor
local bnot = bit32.bnot
local bxor = bit32.bxor
local lsh = bit32.lshift
local rsh = bit32.rshift

local acgreen   = ansicolors.bright..ansicolors.green
local accyan    = ansicolors.bright..ansicolors.cyan
local acred     = ansicolors.red
local acyellow  = ansicolors.bright..ansicolors.yellow
local acblue    = ansicolors.bright..ansicolors.blue
local acmagenta = ansicolors.bright..ansicolors.magenta
local acoff     = ansicolors.reset


-- This is only meant to be used when errors occur
local function oops(err)
    print('ERROR: ', err)
    core.clearCommandBuffer()
    return nil, err
end

local function setdevicedebug( status )
    local c = 'hw dbg '
    if status then
        c = c..'1'
    else
        c = c..'0'
    end
    core.console(c)
end

local function xteaCrypt(num_rounds, v, key)
	local v0 = v[0]
	local v1 = v[1]
	local delta = 0x9E3779B9
	local sum = 0

	for i = 0, num_rounds-1 do
		-- v0 += (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + key[sum & 3]);
		v0 = band(bxor(bxor(lsh(v1,4), rsh(v1,5)) + v1, sum + key[band(sum,3)]) + v0, 0xFFFFFFFF)
		sum = band(sum + delta, 0xFFFFFFFF)
		-- v1 += (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + key[(sum>>11) & 3]);
		v1 = band(bxor(bxor(lsh(v0,4), rsh(v0,5)) + v0, sum + key[band(rsh(sum,11),3)]) + v1, 0xFFFFFFFF)
	end
	v[0]=v0
	v[1]=v1
end

local function xteaDecrypt(num_rounds, v, key)
	local v0 = v[0]
	local v1 = v[1]
	local delta = 0x9E3779B9
	local sum = band(delta * num_rounds, 0xFFFFFFFF)

	for i = 0, num_rounds-1 do
		-- v1 -= (((v0 << 4) ^ (v0 >> 5)) + v0) ^ (sum + key[(sum>>11) & 3]);
		v1 = band(v1 - bxor(bxor(lsh(v0,4), rsh(v0,5)) + v0, sum + key[band(rsh(sum,11),3)]), 0xFFFFFFFF)
		sum = band(sum - delta, 0xFFFFFFFF)
		-- v0 -= (((v1 << 4) ^ (v1 >> 5)) + v1) ^ (sum + key[sum & 3]);
		v0 = band(v0 - bxor(bxor(lsh(v1,4), rsh(v1,5)) + v1, sum + key[band(sum,3)]), 0xFFFFFFFF)
	end
	v[0]=v0
	v[1]=v1
end

local function createxteakey(mfuid)
	local xteakey = {}
	local buid = {}
	local tmpkey = {}
	local uid = {}

	-- Warning ! "it is customary in Lua to START ARRAYS WITH ONE"
	buid = utils.ConvertHexToBytes(mfuid)
	uid[0] = bor(buid[1], lsh(buid[2], 8))
	uid[1] = bor(buid[3], lsh(buid[4], 8))

	tmpkey[0] = 0x198B
	tmpkey[1] = uid[0]
	tmpkey[2] = 0x46D8
	tmpkey[3] = uid[1]
	tmpkey[4] = 0x5310
	tmpkey[5] = bxor(uid[0], 0xA312)
	tmpkey[6] = 0xFFCB
	tmpkey[7] = bxor(uid[1], 0x55AA)

	xteakey[0] = bor(lsh(tmpkey[1], 16), tmpkey[0])
	xteakey[1] = bor(lsh(tmpkey[3], 16), tmpkey[2])
	xteakey[2] = bor(lsh(tmpkey[5], 16), tmpkey[4])
	xteakey[3] = bor(lsh(tmpkey[7], 16), tmpkey[6])

	return xteakey
end

local function getblockdata(response)
    if not response then
        return nil, 'No response from device'
    end
    if response.Status == PM3_SUCCESS then
        return response.Data
    else
        return nil, "Couldn't read block.. ["..response.Status.."]"
    end
end

local function readblock(blockno, key)
    -- Read block N
    local keytype = '01'  -- key B
    local data = ('%02x%s%s'):format(blockno, keytype, key)
    local c = Command:newNG{cmd = cmds.CMD_HF_MIFARE_READBL, data = data}
    local b, err = getblockdata(c:sendNG(false))
    if not b then return oops(err) end
    return b
end

local function readtag(mfkey,xteakey)
	local tagdata = {}
	local cleardata = {}
	local v = {}
	local vv = {}

	-- Read 4 sectors and build table
	for sect = 8, 11 do
		for blockn = sect*4, (sect*4)+2 do
			local blockdata = readblock(blockn, mfkey)
			if not blockdata then return oops('[!] failed reading block') end
			table.insert(tagdata, blockdata)
		end
	end

	-- Decrypt data and build clear table
	for key,value in ipairs(tagdata) do
		local clearblockdata
		v[0]=utils.SwapEndianness(value:sub(1,8),32)
		v[1]=utils.SwapEndianness(value:sub(9,16),32)
		xteaDecrypt(16, v, xteakey)
		vv[0]=utils.SwapEndianness(value:sub(17,24),32)
		vv[1]=utils.SwapEndianness(value:sub(25,32),32)
		xteaDecrypt(16, vv, xteakey)
		clearblockdata=string.format("%08X%08X%08X%08X",
			utils.SwapEndianness(string.format("%08X", v[0]),32),
			utils.SwapEndianness(string.format("%08X", v[1]),32),
			utils.SwapEndianness(string.format("%08X", vv[0]),32),
			utils.SwapEndianness(string.format("%08X", vv[1]),32))
		table.insert(cleardata, clearblockdata)
	end

	return tagdata,cleardata

end


local function main(args)
	local xteakey = {}
	-- local v = {}
	local edata = {}
	local cdata = {}

	-- Turn off Debug
	setdevicedebug(false)

	-- GET TAG UID
	tag, err = lib14a.read(false, true)
	if err then
		lib14a.disconnect()
		return oops(err)
	end
	core.clearCommandBuffer()

	-- simple tag check
	if 0x08 ~= tag.sak then
		if 0x0400 ~= tag.atqa then
			return oops(('[fail] found tag %s :: looking for Mifare S50 1k'):format(tag.name))
		end
	end

	xteakey = createxteakey(tag.uid)
	print(acblue.."UID: "..tag.uid..acoff)
	print(acblue..string.format("XTEA key: %08X %08X %08X %08X", xteakey[0], xteakey[1], xteakey[2], xteakey[3])..acoff)

	edata, cdata = readtag("415A54454B4D",xteakey)

	if edata == nil or cdata == nil then
		print("ERROR Reading tag!")
		return nil
	end

	print("Ciphered data:")
	for key,value in ipairs(edata) do
		print(value)
		if key % 3 == 0 then print("") end
	end

	-- compute CRC for each segment
    crcH = utils.SwapEndianness(core.reveng_runmodel("CRC-16/ARC", cdata[1]..cdata[2]..cdata[3]:sub(1,28), false, '0'),16)
    crcA = utils.SwapEndianness(core.reveng_runmodel("CRC-16/ARC", cdata[4]..cdata[5]..cdata[6]..cdata[7]:sub(1,28), false, '0'),16)
    crcB = utils.SwapEndianness(core.reveng_runmodel("CRC-16/ARC", cdata[8]..cdata[9]..cdata[10]..cdata[11]:sub(1,28), false, '0'),16)

	print("\nHeader:")
	for key,value in ipairs(cdata) do
		if key == 3 then
			print(value:sub(1,28)..acmagenta..value:sub(29,32)..acoff)
			if utils.SwapEndianness(value:sub(29,32),16) == crcH then strcrc = " OK" else strcrc = acred.." CRCERROR !!" end
			print(acmagenta.."CRC16/ARC = "..string.format("0x%04X", crcH)..strcrc..acoff)
			print("\nDataA:")
		elseif key == 4 then
			print(acgreen..value:sub(1,4)..acoff..value:sub(5,16)..accyan..value:sub(17,24)..acoff..value:sub(25,26)..accyan..value:sub(27,28)..acoff..value:sub(29,32))
			versionA = utils.SwapEndianness(value:sub(1,4),16)
			dateA = string.format("%d/%02d/%02d %02d:%02d", tonumber(value:sub(17,18),10)+2000, tonumber(value:sub(19,20),10),
											 tonumber(string.format("%02X", band(tonumber(value:sub(21,22),16),0x3f)),10),
											 tonumber(value:sub(23,24),10), tonumber(value:sub(27,28),10))
		elseif key == 8 then
			print(acgreen..value:sub(1,4)..acoff..value:sub(5,16)..accyan..value:sub(17,24)..acoff..value:sub(25,26)..accyan..value:sub(27,28)..acoff..value:sub(29,32))
			versionB = utils.SwapEndianness(value:sub(1,4),16)
			dateB = string.format("%d/%02d/%02d %02d:%02d", tonumber(value:sub(17,18),10)+2000, tonumber(value:sub(19,20),10),
											 tonumber(string.format("%02X", band(tonumber(value:sub(21,22),16),0x3f)),10),
											 tonumber(value:sub(23,24),10), tonumber(value:sub(27,28),10))
		elseif key == 5 then
			print(acyellow..value:sub(1,4)..acoff..value:sub(5,32))
			creditA = utils.SwapEndianness(value:sub(1,4),16)/100
		elseif key == 9 then
			print(acyellow..value:sub(1,4)..acoff..value:sub(5,32))
			creditB = utils.SwapEndianness(value:sub(1,4),16)/100
		elseif key == 7 then
			print(value:sub(1,28)..acmagenta..value:sub(29,32)..acoff)
			print(acgreen.."Version "..string.format("0x%04X", versionA)..acoff)
			print(acyellow.."Credit : "..creditA..acoff)
			if utils.SwapEndianness(value:sub(29,32),16) == crcA then strcrc = " OK" else strcrc = acred.." CRCERROR !!" end
			print(acmagenta.."CRC16/ARC = "..string.format("0x%04X", crcA)..strcrc..acoff)
			print(accyan.."Date: "..dateA..acoff)
			print("\nDataB:")
		elseif key == 11 then
			print(value:sub(1,28)..acmagenta..value:sub(29,32)..acoff)
			print(acgreen.."Version "..string.format("0x%04X", versionB)..acoff)
			print(acyellow.."Credit : "..creditB..acoff)
			if utils.SwapEndianness(value:sub(29,32),16) == crcB then strcrc = " OK" else strcrc = acred.." CRCERROR !!" end
			print(acmagenta.."CRC16/ARC = "..string.format("0x%04X", crcB)..strcrc..acoff)
			print(accyan.."Date: "..dateB..acoff)
			print("\nFooter:")
		else
			print(value)
		end
	end

	return
end

main(args)
