Is this secure?

[Robert Kern]

On 2010-02-23 13:59 PM, mk wrote:
> On Feb 23, 7:19 pm, Paul Rubin<no.em... at nospam.invalid>  wrote:
>
>> The code is pretty ugly.  The main problem is you end up with a password
>> that's usually 5 letters but sometimes just 4 or fewer.
>
> Well I didn't write the whole thing here, in actual use I'd write a
> loop repeating the function until I have enough characters and then
> I'd select a substring of specified length.
>
> Anything else in the code that is ugly and I should correct?

I would recommend using random.SystemRandom.choice() on a sequence of acceptable 
characters. E.g. (untested)

import random
import string


characters = string.letters + string.digits + '~!@#$%^&*()-+=,;./\?><|'
# ... or whatever.

def gen_rand_string(length):
     prng = random.SystemRandom()
     chars = []
     for i in range(length):
         chars.append(prng.choice(characters))
     return ''.join(chars)

-- 
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
  that is made terrible by our own mad attempt to interpret it as though it had
  an underlying truth."
   -- Umberto Eco