git.zerfleddert.de Git - proxmark3-svn/blob - client/scripts/calc_ev1_it.lua

   1 local bin = require('bin')
   2 local getopt = require('getopt')
   3 local utils =  require('utils')
   4
   5 local bxor=bit32.bxor
   6
   7 example =[[
   8          script run calc_ev1_it
   9          script run calc_ev1_it -u 11223344556677
  10 ]]
  11 author = "Iceman"
  12 usage = "script run calc_ev1_it -u <uid> "
  13 desc =[[
  14 Arguments:
  15         -h             : this help
  16         -u <UID>       : UID
  17 ]]
  18 ---
  19 -- A debug printout-function
  20 function dbg(args)
  21     if type(args) == "table" then
  22                 local i = 1
  23                 while args[i] do
  24                         dbg(args[i])
  25                         i = i+1
  26                 end
  27         else
  28                 print("###", args)
  29         end
  30 end
  31 ---
  32 -- This is only meant to be used when errors occur
  33 function oops(err)
  34         print("ERROR: ",err)
  35         return nil,err
  36 end
  37 ---
  38 -- Usage help
  39 function help()
  40         print(desc)
  41         print("Example usage")
  42         print(example)
  43 end
  44 --
  45 -- Exit message
  46 function exitMsg(msg)
  47         print( string.rep('--',20) )
  48         print( string.rep('--',20) )
  49         print(msg)
  50         print()
  51 end
  52
  53 local _xortable = {
  54     --[[ position, 4byte xor
  55     --]]
  56         {"00","4f2711c1"},
  57         {"01","07D7BB83"},
  58         {"02","9636EF07"},
  59         {"03","B5F4460E"},
  60         {"04","F271141C"},
  61         {"05","7D7BB038"},
  62         {"06","636EF871"},
  63         {"07","5F4468E3"},
  64         {"08","271149C7"},
  65         {"09","D7BB0B8F"},
  66         {"0A","36EF8F1E"},
  67         {"0B","F446863D"},
  68         {"0C","7114947A"},
  69         {"0D","7BB0B0F5"},
  70         {"0E","6EF8F9EB"},
  71         {"0F","44686BD7"},
  72         {"10","11494fAF"},
  73         {"11","BB0B075F"},
  74         {"12","EF8F96BE"},
  75         {"13","4686B57C"},
  76         {"14","1494F2F9"},
  77         {"15","B0B07DF3"},
  78         {"16","F8F963E6"},
  79         {"17","686B5FCC"},
  80         {"18","494F2799"},
  81         {"19","0B07D733"},
  82         {"1A","8F963667"},
  83         {"1B","86B5F4CE"},
  84         {"1C","94F2719C"},
  85         {"1D","B07D7B38"},
  86         {"1E","F9636E70"},
  87         {"1F","6B5F44E0"},
  88 }
  89
  90 local function findEntryByUid( uid )
  91
  92         -- xor UID4,UID5,UID6,UID7
  93         -- mod 0x20 (dec 32)
  94         local pos = (bxor(bxor(bxor(uid[4],uid[5]), uid[6]),uid[7])) % 32
  95
  96         -- convert to hexstring
  97         pos = string.format('%02X', pos)
  98
  99     for k, v in pairs(_xortable) do
 100                 if ( v[1]  == pos ) then
 101                         return utils.ConvertHexToBytes(v[2])
 102                 end
 103         end
 104         return nil
 105 end
 106
 107 local function main(args)
 108
 109         print( string.rep('--',20) )
 110         print( string.rep('--',20) )
 111         print()
 112
 113         local i,j, pwd
 114         local uid = '04111211121110'
 115
 116         -- Arguments for the script
 117         for o, a in getopt.getopt(args, 'hu:') do
 118                 if o == "h" then return help() end
 119                 if o == "u" then uid = a end
 120         end
 121
 122         -- uid string checks
 123         if uid == nil then return oops('empty uid string') end
 124         if #uid == 0 then return oops('empty uid string') end
 125         if #uid ~= 14 then return oops('uid wrong length. Should be 7 hex bytes') end
 126
 127         local uidbytes = utils.ConvertHexToBytes(uid)
 128
 129     local entry = findEntryByUid(uidbytes)
 130         if entry == nil then return oops("Can't find a xor entry") end
 131
 132         --  PWD CALC
 133         --      PWD0  =  T0 xor B xor C xor D
 134         --      PWD1  =  T1 xor A xor C xor E
 135         --      PWD2  =  T2 xor A xor B xor F
 136         --      PWD3  =  T3 xor G
 137
 138     local pwd0 = bxor( bxor( bxor( entry[1], uidbytes[2]), uidbytes[3]), uidbytes[4])
 139         local pwd1 = bxor( bxor( bxor( entry[2], uidbytes[1]), uidbytes[3]), uidbytes[5])
 140         local pwd2 = bxor( bxor( bxor( entry[3], uidbytes[1]), uidbytes[2]), uidbytes[6])
 141         local pwd3 = bxor( entry[4], uidbytes[7])
 142
 143         print('UID | '..uid)
 144         print(string.format('PWD | %02X%02X%02X%02X', pwd0, pwd1, pwd2, pwd3))
 145 end
 146
 147 main(args)