RE: os authenticated accounts

From: QuijadaReina, Julio C <>
Date: Wed, 5 Mar 2008 10:01:55 -0500
Message-ID: <>


You bring out excellent points. I agree about the security concern here. I believe Metalink 401251.1 shows one of those secure alternatives. One would actually need the Oracle Wallet Manager and orapki and avoid having to use a Certifcate Authority.


From: [] On Behalf Of Mark Brinsmead [] Sent: Wednesday, March 05, 2008 12:18 AM To:
Subject: Re: os authenticated accounts

Is checking the source IP in a trigger reliable?

I do not recall the source, but I had the impression that that information is provided (directly) by the client, not by the TNS listener, and can (relatively) easily be spoofed. Also, the method would break down -- or be tricked -- when using "proxied" connections, e.g., port-forwarding through SSH, or possibly Oracle Connection Manager. (Never used the latter myself.) It would also be problematic if there are NAT-enabled firewalls anywhere along your network route.

Every case needs to be judged on its own merits, but basically it is my practice to award REMOTE_OS_AUTHENTICATION=TRUE an automatic "Fail" on any security review, even (or especially) where there are no EXTERNALLY IDENTIFIED accounts present in the database. While I have never actually attempted to "hack" or "spoof" it, my understanding is that it is all too easy.

For those who can afford it, though, the Advanced Security Option and/or Database Vault offer secure alternatives, I believe. I have stumbled across these options myself while answering similar questions, but it has been so many years since I've been at a site with pockets deep enough (or business needs serious enough) to actually consider these expensive options, I have never really investigated them in any real depth.

*sigh* Working for regulated utilities did have its advantages... :-)

Of course, the O.P. only asked "is this possible?", and the answer is "yes, it certainly is". What a shame he did not ask instead "is this wise?".


On Tue, Mar 4, 2008 at 12:02 PM, Powell, Mark D <<>> wrote:

I have always preferred to set the os_authent_prefix='' rather than OPS$. I am not sure if trying to limit the node access is practical since I do not think the node checking can be associated to usernames in the sqlnet layer. You might need to resort to checking the IP for any OS authenticated accounts in an after logon database event trigger.

  • Mark D Powell -- Phone (313) 592-5148

-----Original Message-----
From:<> [<>] On Behalf Of QuijadaReina, Julio C
Sent: Tuesday, March 04, 2008 9:52 AM
To: '<>';<> Cc:<> Subject: RE: os authenticated accounts

Yes, it is possible.
The following parameters on your database init.ora relating to this are (if my memory serves me correctly):

Create the account you will use on your Linux box. Then create the externally identified account on your database. From your Linux client you should be able to connect by issuing 'sqlplus /' after setting the client environment.

A word of caution: anyone knowing your database tnsnames and the name of the account could potentially connect to your database. That sounds pretty bad! You might want to look into tcp.validnode_checking and tcp.invited_nodes pars on your server's sqlnet.ora and/or have the OS firewall setting that opens the listener port only to your linux client.


-----Original Message-----
From:<> [<>] On Behalf Of Maxim Demenko Sent: Tuesday, March 04, 2008 1:05 AM
To:<> Cc:<> Subject: Re: os authenticated accounts

Joe Smith schrieb:
> Is it possible to use OS authenticated accounts ( i.e. identified
> externally ) between two servers?


> I have a linux box with with an oracle client install and an aix
> server with EE installed.

> The external account was originally on the aix server. We want to
> move the 3rd party app and the account to a linux box.

> thanks.

> ----------------------------------------------------------------------
> -- Shed those extra pounds with MSN and The Biggest Loser! Learn more.
> <>

You may look on the external users identified by ssl certificates (if you are on 10g onwards).
Not sure about additional licensing costs (i.e. whether it is part of ASO or not).

Best regards





-- Mark Brinsmead
  Senior DBA,
  The Pythian Group
Received on Wed Mar 05 2008 - 09:01:55 CST

Original text of this message