code.delx.au - pymsnt/blob - src/legacy/msn/msnp11chl.py

   1 # Copyright 2005 James Bunton <james@delx.cjb.net>
   2 # Licensed for distribution under the GPL version 2, check COPYING for details
   3
   4 import md5
   5 import struct
   6
   7 MSNP11_PRODUCT_ID = "PROD0090YUAUV{2B"
   8 MSNP11_PRODUCT_KEY = "YMM8C_H7KCQ2S_KL"
   9 MSNP11_MAGIC_NUM = 0x0E79A9C1
  10
  11
  12 def doChallenge(chlData):
  13         md5digest = md5.md5(chlData + MSNP11_PRODUCT_KEY).digest()
  14
  15         # Make array of md5 string ints
  16         md5Ints = struct.unpack("<llll", md5digest)
  17         md5Ints = [(x & 0x7fffffff) for x in md5Ints]
  18
  19         # Make array of chl string ints
  20         chlData += MSNP11_PRODUCT_ID
  21         amount = 8 - len(chlData) % 8
  22         chlData += "".zfill(amount)
  23         chlInts = struct.unpack("<%di" % (len(chlData)/4), chlData)
  24
  25         # Make the key
  26         high = 0
  27         low = 0
  28         i = 0
  29         while i < len(chlInts) - 1:
  30                 temp = chlInts[i]
  31                 temp = (MSNP11_MAGIC_NUM * temp) % 0x7FFFFFFF
  32                 temp += high
  33                 temp = md5Ints[0] * temp + md5Ints[1]
  34                 temp = temp % 0x7FFFFFFF
  35
  36                 high = chlInts[i + 1]
  37                 high = (high + temp) % 0x7FFFFFFF
  38                 high = md5Ints[2] * high + md5Ints[3]
  39                 high = high % 0x7FFFFFFF
  40
  41                 low = low + high + temp
  42
  43                 i += 2
  44
  45         high = littleEndify((high + md5Ints[1]) % 0x7FFFFFFF)
  46         low = littleEndify((low + md5Ints[3]) % 0x7FFFFFFF)
  47         key = (high << 32L) + low
  48         key = littleEndify(key, "Q")
  49
  50         longs = [x for x in struct.unpack(">QQ", md5digest)]
  51         longs = [littleEndify(x, "Q") for x in longs]
  52         longs = [x ^ key for x in longs]
  53         longs = [littleEndify(abs(x), "Q") for x in longs]
  54
  55         out = ""
  56         for x in longs:
  57                 x = hex(x)
  58                 x = x[2:].strip("L")
  59                 x = x.zfill(16)
  60                 out += x.lower()
  61
  62         return out
  63
  64 def littleEndify(num, c="L"):
  65         return struct.unpack(">" + c, struct.pack("<" + c, num))[0]
  66
  67
  68 if __name__ == "__main__":
  69         import sys
  70         try:
  71                 print doChallenge(sys.argv[1])
  72         except IndexError:
  73                 print "No args passed"
  74                 raise
  75