From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Stephen Frost <sfrost@snowman.net>, Josh Berkus <josh@agliodbs.com>,
 Kohei KaiGai <kaigai@kaigai.gr.jp>, "ktm@rice.edu" <ktm@rice.edu>,
 Alexander Korotkov <aekorotkov@gmail.com>,
 Oleg Bartunov <obartunov@gmail.com>, Greg Smith <greg@2ndquadrant.com>,
 PgHacker <pgsql-hackers@postgresql.org>
Subject: Re: [v9.4] row level security
In-reply-to: 
 <CA+TgmobRiYj8NCb4Lra5-MzvjnVKz6OrYSsn-Z04YJGsmiQAsg@mail.gmail.com>
References: 
 <CADyhKSWkHrPqbRsFK0LjPMOOTsbKGWOuN75GqYJrxCDO3CKWtA@mail.gmail.com>
 <CAPpHfdsgMrBnzu9um48O6kwY=_pRFuRrBrHqnA03fCAo8x3-Gg@mail.gmail.com>
 <CADyhKSUpcYKNm3rQRwCFqkTZfO3_ZrqYKjAqDxKeA6WeLezSbw@mail.gmail.com>
 <20130829142321.GA30496@aart.rice.edu>
 <CADyhKSUD7qdQeTndZ6mDpp05V6MnRBzQO1FmYBq1+Zp37oyRrg@mail.gmail.com>
 <WM!685df689dd4d8f8c5349d5ef7b8e285db1e99ea32d22ab5d35f3981c29eac19dbd725c9b5e0227def9d782de274d1354!@asav-3.01.com>
 <521F7DFB.8060602@agliodbs.com>
 <CADyhKSW_o2nVWFytdTY84DUXZSuZkD_EtY2d8wAjR18UruOXYQ@mail.gmail.com>
 <WM!fb94ecb91cd381e69d8e4773d3810f48e4e0ef000525cc806c4ee509f215ce1a39c8c2a1c3ffde72ba2ddb1a07ebcdc9!@asav-2.01.com>
 <5220D832.7090104@agliodbs.com> <20130830192729.GO2706@tamriel.snowman.net>
 <16798.1377891794@sss.pgh.pa.us>
 <CA+TgmoZYv_me1iB6iDRA_oO-o9xkxXYqr-0UtwK5itpZbDsqYA@mail.gmail.com>
 <1398.1378305956@sss.pgh.pa.us>
 <CA+TgmoYTf+4RUOW8stVz1RE+3TD+QR5TNKzYuFDCehSkieL5OQ@mail.gmail.com>
 <1543.1378306249@sss.pgh.pa.us> <CA+TgmobRiYj8NC!
 b4Lra5-MzvjnVKz6OrYSsn-Z04YJGsmiQAsg@mail.gmail.com>
Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
 message dated "Wed, 04 Sep 2013 11:03:34 -0400"
Date: Wed, 04 Sep 2013 11:22:39 -0400
Message-ID: <2620.1378308159@sss.pgh.pa.us>
Precedence: bulk
Sender: pgsql-hackers-owner@postgresql.org

Robert Haas <robertmhaas@gmail.com> writes:
> On Wed, Sep 4, 2013 at 10:50 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Robert Haas <robertmhaas@gmail.com> writes:
>>> Right.  IMHO, this new feature should be similarly simple: when an
>>> unprivileged user references a table, treat that as a reference to a
>>> leakproof view over the table, with the RLS qual injected into the
>>> view.

>> And for insert/update/delete, we do what exactly?

> The same mechanism will prevent UPDATE and DELETE from seeing any rows
> the user shouldn't be able to touch.

No, it won't, because we don't support direct update/delete on views
(and if you look, you'll notice the auto-updatable-view stuff doesn't
think a security-barrier view is auto-updatable).

AFAICT, to deal with update/delete the RLS patch needs to constrain order
of qual application without the crutch of having a separate level of
subquery; and it's that behavior that I have zero confidence in, either
as to whether it works as submitted or as to our odds of not breaking it
in the future.

			regards, tom lane


-- 
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers