Re: [HACKERS] Solution to the pg_user passwd problem !?? (c)

>
> Hi all,
>
> What about:
> grant select on pg_user to public;
> create rule pg_user_hide_pw as on
> select to pg_user.passwd
> do instead select '********' as passwd;
>
> Then if I do:
> select * from pg_user;
> usename |usesysid|usecreatedb|usetrace|usesuper|usecatupd|passwd  |valuntil
> --------+--------+-----------+--------+--------+---------+--------+---------
> -------------------
> postgres|       6|t          |t       |t       |t        |********|Sat Jan
> 31 07:00:00 2037 NFT
> zeus    |      60|t          |t       |f       |t        |********|
> (2 rows)
>
> Also the \d works for all users !
>
> Only "disadvantage" is that noone can read passwd without first dropping the
> rule pg_user_hide_pw,
> I consider this a feature though ;-)
>
> Since the userauthentication bypasses the rewrite mechanism the logins,
> alter user .. and others do work !
>
> Can all of you try to crack this ?

    Cracked!

    create table get_passwds (usename name, passwd text);
    insert into get_passwds select usename, passwd from pg_user;
    select * from get_passwds;
    usename|passwd
    -------+------
    pgsql  |
    wieck  |test
    (2 rows)



Sorry, Jan

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