ADD: a minor xor script

client/scripts/calc_ev1_it.lua

@@ -0,0 +1,147 @@
+local bin = require('bin')
+local getopt = require('getopt')
+local utils =  require('utils')
+
+local bxor=bit32.bxor
+
+example =[[
+	 script run calc_ev1_it
+	 script run calc_ev1_it -u 11223344556677
+]]
+author = "Iceman"
+usage = "script run calc_ev1_it -u <uid> "
+desc =[[
+Arguments:
+	-h             : this help
+	-u <UID>       : UID
+]]
+--- 
+-- A debug printout-function
+function dbg(args)
+    if type(args) == "table" then
+		local i = 1
+		while args[i] do
+			dbg(args[i])
+			i = i+1
+		end
+	else
+		print("###", args)
+	end	
+end	
+--- 
+-- This is only meant to be used when errors occur
+function oops(err)
+	print("ERROR: ",err)
+	return nil,err
+end
+--- 
+-- Usage help
+function help()
+	print(desc)
+	print("Example usage")
+	print(example)
+end
+--
+-- Exit message
+function exitMsg(msg)
+	print( string.rep('--',20) )
+	print( string.rep('--',20) )
+	print(msg)
+	print()
+end
+
+local _xortable = {
+    --[[ position, 4byte xor
+    --]]
+	{"00","4f2711c1"},
+	{"01","07D7BB83"},
+	{"02","9636EF07"},
+	{"03","B5F4460E"},
+	{"04","F271141C"},
+	{"05","7D7BB038"},
+	{"06","636EF871"},
+	{"07","5F4468E3"},
+	{"08","271149C7"},
+	{"09","D7BB0B8F"},
+	{"0A","36EF8F1E"},
+	{"0B","F446863D"},
+	{"0C","7114947A"},
+	{"0D","7BB0B0F5"},
+	{"0E","6EF8F9EB"},
+	{"0F","44686BD7"},
+	{"10","11494fAF"},
+	{"11","BB0B075F"},
+	{"12","EF8F96BE"},
+	{"13","4686B57C"},
+	{"14","1494F2F9"},
+	{"15","B0B07DF3"},
+	{"16","F8F963E6"},
+	{"17","686B5FCC"},
+	{"18","494F2799"},
+	{"19","0B07D733"},
+	{"1A","8F963667"},
+	{"1B","86B5F4CE"},
+	{"1C","94F2719C"},
+	{"1D","B07D7B38"},
+	{"1E","F9636E70"},
+	{"1F","6B5F44E0"},
+}
+
+local function findEntryByUid( uid )
+
+	-- xor UID4,UID5,UID6,UID7
+	-- mod 0x20 (dec 32)
+	local pos = (bxor(bxor(bxor(uid[4],uid[5]), uid[6]),uid[7])) % 32
+
+	-- convert to hexstring
+	pos = string.format('%02X', pos)
+	
+    for k, v in pairs(_xortable) do
+		if ( v[1]  == pos ) then
+			return utils.ConvertHexToBytes(v[2])
+		end
+	end
+	return nil
+end
+
+local function main(args)
+
+	print( string.rep('--',20) )
+	print( string.rep('--',20) )	
+	print()
+			
+	local i,j, pwd
+	local uid = '04111211121110'
+	
+	-- Arguments for the script
+	for o, a in getopt.getopt(args, 'hu:') do
+		if o == "h" then return help() end		
+		if o == "u" then uid = a end		
+	end
+
+	-- uid string checks
+	if uid == nil then return oops('empty uid string') end
+	if #uid == 0 then return oops('empty uid string') end
+	if #uid ~= 14 then return oops('uid wrong length. Should be 7 hex bytes') end
+
+	local uidbytes = utils.ConvertHexToBytes(uid)
+
+    local entry = findEntryByUid(uidbytes)
+	if entry == nil then return oops("Can't find a xor entry") end
+
+	--  PWD CALC	
+	--	PWD0  =  T0 xor B xor C xor D
+	--	PWD1  =  T1 xor A xor C xor E 
+	--	PWD2  =  T2 xor A xor B xor F 
+	--	PWD3  =  T3 xor G 
+  
+    local pwd0 = bxor( bxor( bxor( entry[1], uidbytes[2]), uidbytes[3]), uidbytes[4])
+	local pwd1 = bxor( bxor( bxor( entry[2], uidbytes[1]), uidbytes[3]), uidbytes[5])
+	local pwd2 = bxor( bxor( bxor( entry[3], uidbytes[1]), uidbytes[2]), uidbytes[6])
+	local pwd3 = bxor( entry[4], uidbytes[7])
+	
+	print('UID | '..uid)
+	print(string.format('PWD | %02X%02X%02X%02X', pwd0, pwd1, pwd2, pwd3))
+end
+
+main(args)