Re: Updates of SE-PostgreSQL 8.4devel patches (r1168) - Mailing list pgsql-hackers

Bruce Momjian wrote:
> KaiGai Kohei wrote:
>> I've updated my patches, it contains a few bugfixes.
>>
>> [1/6] http://sepgsql.googlecode.com/files/sepostgresql-sepgsql-8.4devel-3-r1168.patch
>> [2/6] http://sepgsql.googlecode.com/files/sepostgresql-pg_dump-8.4devel-3-r1168.patch
>> [3/6] http://sepgsql.googlecode.com/files/sepostgresql-policy-8.4devel-3-r1168.patch
>> [4/6] http://sepgsql.googlecode.com/files/sepostgresql-docs-8.4devel-3-r1168.patch
>> [5/6] http://sepgsql.googlecode.com/files/sepostgresql-tests-8.4devel-3-r1168.patch
>> [6/6] http://sepgsql.googlecode.com/files/sepostgresql-row_acl-8.4devel-3-r1168.patch
>>
>> The comprehensive documentation for SE-PostgreSQL is here:
>>    http://wiki.postgresql.org/wiki/SEPostgreSQL (it is now under reworking.)
>>
>> List of updates:
>> - Patches are rebased to the latest CVS HEAD.
>> - bugfix: permission checks are ignored for per statement trigger functions
>> - bugfix: per-statement trigger function ignored trusted function configuration
>> - bugfix: not a proper permission check on lo_export(xxx, '/dev/null')
>>
>>> Request for Comments:
>>> - The 4th patch is actually needed? It can be replaced by wiki page.
>>> - Do you think anything remained towards the final CommitFest?
>>> - Do you have any reviewing comment? Most of patches are unchanged from
>>>   the previous vesion. If you can comment anything, I can fix them without
>>>   waiting for the final commit fest.
> 
> I just looked over the patch.  This new version with row-level SQL
> security has certainly reduced the SE-Linux-specific part, which is
> good.
> 
> It was interesting how you implemented SQL-level column-level
> permissions:
> 
>     CREATE TABLE customer (
>         cid     integer primary key,
>         cname   varchar(32),
>         credit  varchar(32)  SECURITY_CONTEXT = 'system_u:object_r:sepgsql_secret_table_t'
>     );
> 
> I am unclear how that will behave with the column-level permissions
> patch someone is working on.  I am wondering if your approach is clearer
> than the other patch because it gives a consistent right policy for rows
> and columns.

The column-level permissions in SE-PostgreSQL works independently and
orthogonally from the upcoming column-level permissions by Stephen Frost.
When the SE-PostgreSQL is enabled, both of facilities have to allow the
client to access required columns.

In the above case, the "credit" column has "sepgsql_secret_table_t" type,
but rest of columns inherits the type of "customer" table which allows
non-administrative users to access in the default security policy.
If the given query contains the "credit" column, SE-PostgreSQL checks
privileges of client to access columns labeled as "sepgsql_secret_table_t",
then it raises an error to abort the current transaction if the security
policy does not allow it.

There is a possibility that column-level ACLs are set via newer GRANT/REVOKE
statement. In this case, the core PostgreSQL checks them, and raises an error
if violated.


> I was wondering why you mention the NSA (U.S. National Security Agency)
> in the patch?
> 
>     +# NSA SELinux support

The original author of SELinux is NSA.
There is no more meanings than a caption of the option.
I'll fix it, if necessary.


> The size of the patch is still larger but I don't see any way to reduce it:
> 
>     1275 sepostgresql-docs-8.4devel-3-r1168.patch
>      625 sepostgresql-pg_dump-8.4devel-3-r1168.patch
>      829 sepostgresql-policy-8.4devel-3-r1168.patch
>     1736 sepostgresql-row_acl-8.4devel-3-r1168.patch
>    10847 sepostgresql-sepgsql-8.4devel-3-r1168.patch
>     1567 sepostgresql-tests-8.4devel-3-r1168.patch
>    16879 total

I thought the "sepostgresql-docs" can be replaced by the pointing to the wiki
page, how do you think the idea?

Thanks,
-- 
KaiGai Kohei <kaigai@kaigai.gr.jp>