Date: Wed, 9 Nov 2016 09:59:27 +0300
From: Victor Wagner <vitus@wagner.pp.ru>
To: PostgreSQL mailing lists <pgsql-hackers@postgresql.org>
Subject: Re: Password identifiers, protocol aging and SCRAM
 protocol
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On Wed, 9 Nov 2016 15:23:11 +0900
Michael Paquier <michael.paquier@gmail.com> wrote:


> 
> (This is about patch 0007, not 0001)
> Thanks, you are right. That's not good as-is. So this basically means
> that the characters here should be from 32 to 127 included.

Really, most important is to exclude comma from the list of allowed
characters. And this prevents us from using a range.

I'd do something like:

char prinables="0123456789ABCDE...xyz!@#*&+";
unsigned int r;

for (i=0;i<SCRAM_NONCE_SIZE;i++) {
     pg_strong_random(&r,sizeof(unsigned int))
     nonce[i]=printables[r%(sizeof(prinables)-1)]
     /* -1 is here to exclude terminating zero byte*/
}
    

> generate_nonce needs just to be made smarter in the way it selects the
> character bytes.


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