RE: [security-services] AuthenticationMethod / NameIdentifier and Kerberos authentication

From
Tim Alsop <>
Date
2004-04-12T20:51:39+00:00
ID
Thread
RE: [security-services] AuthenticationMethod / NameIdentifier and Kerberos authentication
Title: RE: [security-services] AuthenticationMethod / NameIdentifier and Kerberos authentication

Ah, I think I understand what you are saying now.

So, instead of making the preauth data type part of the Authentication Method you are suggesting an Authentication Context statement is used instead ? If this is a roughly correct interpretation of your suggestion, then I agree. This approach will also allow for other authentication method context details to be provided such as validity period :-)

Thanks, Tim.

-----Original Message-----

From: John Kemp [mailto:] 

Sent: 12 April 2004 22:01

To: ext Tim Alsop

Cc: Scott Cantor; John Hughes; 

Subject: Re: [security-services] AuthenticationMethod / NameIdentifier and Kerberos authentication

ext Tim Alsop wrote:

> John,

>

> The RFC1510 defines the Kerberos standard, and more recently has been 

> updated to create an rfc1510bis (known as Kerberos clarifications). It 

> is possible that rfc1510bis will eventually result in a new rfc number 

> for the Kerberos protocol that will supersede rfc1510, but I am not 

> 100% sure what the plans or conventions are with this. I can find out 

> for sure if you think it might be important ?

>

> So, I wondered whether rfc1510 should be referenced in the assertion, 

> and perhaps we should consider using the word "Kerberos" instead in 

> the AuthMethod ?

>

I think I tend to agree with you, if there will be at least two RFCs 

that may be implemented to provide Krb support. Unless we need to 

support indication of which RFC is adhered to in the authentication 

method (for IOP purposes perhaps), we would probably be better off 

defining an SSTC authentication method for Krb that is "RFC-agnostic".

> Anyway, various authentication methods are defined in complementary 

> drafts or RFC's and each have their own pre-auth data type. The basic 

> pre-auth types (e.g. userid/password) are described in rfc1510 and 

> rfc1510bis.

>

> This whole approach is being reviewed at the moment and a new draft 

> was recently created to better structure the way multiple 

> pre-authentication methods are implemented (see 

> http://www.ietf.org/internet-drafts/draft-ietf-krb-wg-preauth-framework-00.txt).

>

Thanks for the reference - I'll take a look at this.

>  

> So, answering your specific questions :

>

> - Pre-authentication is optional, but it is not very common to disable 

> it since it improves security when enabled.

>

OK - but whether it took place, and how it took place is contextual 

information pertaining to the Kerberos authentication event. As such, it 

probably should be encapsulated as authentication context statements 

specific to the Kerberos authentication method.

> - Yes, your interpretation looks correct to me except that you should 

> use the word 'pre-authentication' instead of 'authentication'.

>

OK thanks.

Cheers,

- JohnK