Re: Patch to make postmaster bind to only to localhost. - Mailing list pgsql-patches

Bruce,

I might agree accept for the following.  By the time the pg_hba.conf
file is checked the connection is already accepted, then rejected
by the rule.  A outsider could easlily over-load the postmaster by
making repeated connections.

Also with a port scan a outside cracker can get a small peice of
information about what is running on your system.  The less information
a cracker has the beter.

With this patch both of these situitations would not be possible.

Would you be more open to a more general, but more complex, patch that
would allow you to select the IP's that you bind to.  This would allow
one to configure a system where the localhost, and an internal interface
are bound, but the external interface to the internet is not.

Thanks,

John C. Quillan
>
> I am inclinded to skip this patch.  We already have too many postmaster
> options, and I don't think adding something that already is done in
> pg_hba.conf is a big help.  Sorry.
>
> > All,
> >
> > The company I work, DataSoft, for is doing a web based project
> > that uses Java and the JDBC driver for postgres.  Aperently the
> > developers have told me that the JDBC requires the -i option on
> > postmaster. The only problem is this leves a visibility to the
> > outside world that we are using postmaster, or some other service.
> > Now we do have the pg_hba.conf configured to allow connections
> > from only that box it self, but you can never be two parinoid.
> >
> > The patch that is attached adds a "-L" option to postmaster, which
> > tells postmaster to bind only to 127.0.0.1 or localhost.  Now this
> > port is not exposed to the outside world, ie port scanners can't
> > detect it, and we can run our Java code with a little more comfort.
> >
> > The patch is against the postgresql-7.0.2 source tree.
> >
> > The patch was minimally test under Linux kernel 2.2.5 using
> > a RedHat 6.0 distribution.
> >
> > The files effected are
> >   postgresql-7.0.2/src/backend/libpq/pqcomm.c
> >   postgresql-7.0.2/src/include/libpq/libpq.h
> >   postgresql-7.0.2/src/backend/postmaster/postmaster.c
> >
> > The patch just addes the -L option with a bool flag variable
> > BindLocalOnly to postmaster.c
> >
> > Also the StreamServerPort function was modified to tha an extra
> > bool arguement which then if true causes the socket to be bound
> > to INADDR_LOOPBACK instead of INADDR_ANY.
> >
> > The patch is just a tar.gz file that extracts over the postgresql-7.0.2
> > source tree.
> >
> > If there are any issues pleas let me know.
> >
> > Thanks,
> >
> > John C. Quillan
> > john_quillan@datasoft.com
>
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>
> --
>   Bruce Momjian                        |  http://candle.pha.pa.us
>   pgman@candle.pha.pa.us               |  (610) 853-3000
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