mdw@git.distorted.org.uk Git - mLib/blob - hash/t/unihash-testgen.py

   1 #! /usr/bin/python
   2 ### -*-python-*-
   3 ###
   4 ### Generate test vectors for universal hashing.
   5
   6 MOD = 0x104c11db7
   7
   8 def gfmul(x, y):
   9   a = 0
  10   while y > 0:
  11     if y & 1: a ^= x
  12     if x & 0x80000000: x = (x << 1) ^ MOD
  13     else: x <<= 1
  14     y >>= 1
  15   return a
  16
  17 def hashtest(k, m):
  18   h = k
  19   for ch in m: h = gfmul(h ^ ord(ch), k)
  20   print '  0x%08x "%s" 0x%08x;' % (k, m, h)
  21
  22 print '''\
  23 ### Test vectors for universal hashing
  24 ###   [generated]
  25
  26 hash {'''
  27
  28 for k, m in [(0x00000000, 'anything you like'),
  29              (0x12345678, 'an exaple test string'),
  30              (0xb8a171f0, 'The quick brown fox jumps over the lazy dog.'),
  31              (0x2940521b, 'A man, a plan, a canal: Panama!')]:
  32   hashtest(k, m)
  33
  34 k, m = 0x94b22a73, 0xbb7b1fef
  35 for i in xrange(48):
  36   hashtest(k, "If we don't succeed, we run the risk of failure.")
  37   k = gfmul(k, m)
  38
  39 print '}'