test, and password generator

[Will Ware]

I'm tinkering with my email and usenet service, for which this is
a test. ObPython follows.

#!/usr/bin/env python
# handy password generator
import random, math

if 0:
     # short, cryptic passwords with rich character set
     # To avoid confusion, leave out 0, O, 1, and l.
     units = "ABCDEFGHIJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz23456789"
     units = units + """!@#$%^&*+=;:,.""" # Compensate with punctuation.
     separator = ""
elif 1:
     # short cryptic passwords with lowercase and digits only
     units = "abcdefghijkmnopqrstuvwxyz0123456789"
     separator = ""
else:
     # long passwords made from real words
     # These are OK with Unix, bad with Windows.
     units = [ ]
     separator = "-"
     inf = open("/usr/dict/words")
     for x in inf.readlines():
         units.append(x[:-1])
     inf.close()

length = 10

e = length * math.log(len(units)) / math.log(2)
print "Entropy is %g bits" % e
# Assume the attacker attempts 100 logins per second, but can't get
# access to /etc/passwd or /etc/shadow. Then...
print "Cracking time is", (0.01 * 2**e) / (3600 * 24 * 365.24), "years"

pw = ""
for i in range(length):
     pw = pw + random.choice(units) + separator
if len(separator):
     pw = pw[:-len(separator)]

print "Password:", pw