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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Tue, 7 Jun 2011 14:58:50 -0600
Subject: Re: How good is security via hashing
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On Tue, Jun 7, 2011 at 2:42 PM, Paul Rubin <no.email@nospam.invalid> wrote:
> geremy condra <debatem1@gmail.com> writes:
>> # adds random junk to the filename- should make it hard to guess
>> rrr =3D os.urandom(16)
>> fname +=3D base64.b64encode(rrr)
>
> Don't use b64 output in a filename -- it can have slashes in it! =A0:-(
>
> Simplest is to use old fashioned hexadeimal for stuff like that, unless
> the number of chars is a significant problem. =A0Go for a more complicate=
d
> encoding if you must.

You can use base64.urlsafe_b64encode, or specify a custom altchars
argument that doesn't include '/'.

Definitely don't use base64 filenames on a case-insensitive
filesystem, though. :-)