> -----Original Message-----
> From: Sam Hartman [mailto:[email protected]]
> Sent: Sunday, October 30, 2011 4:20 PM
> To: Jim Schaad
> Cc: [email protected]; [email protected]
> Subject: Re: [abfab] Review on gss-eap-03
> 
> >>>>> "Jim" == Jim Schaad <[email protected]> writes:
> 
> 
>     Jim> Is the ABNF for "name" still wrong?
> 
> I don't think so.
> What problem or oddity do you see?
> Hmm.
> I see that realm is only permitted if host is present. I think I've fixed
that.
> I think it's correct now in 04.

That was the specific error that I saw.

> 
> 
>     Jim> section 3.4 missing
> 
>     Jim> Section 4 - does/should the application get any control ovret
>     Jim> the set of allowable EAP methods to be used or is that purely a
>     Jim> fucntion of your GSS-API library
> 
> Currently no mechanism is provided for an application to enfluence this.
> A mechanism probably should have system-level policy configuration.
> A mechanism could expose a credential option on the initiator.
> If we ever need to standardize a credential option we can, but I don't see
a
> need for that now.
> 
> 
> 
>     Jim> For consistency the paragraph: Tokens from the initiator to
>     Jim> acceptor use an outer token type of 06 01; tokens from acceptor
>     Jim> to initiator use an outer token type of 06 02.  These token
>     Jim> types are registered in the registry of RFC 4121 token types;
>     Jim> see Section 8.1.
> 
> My understanding is that the ID describes which type of token (token
> type) we are dealing with.
> So, I've phrased it as token s with from acceptor to initiator use  an
inner
> token type with ID xxx.
> 1) token type with ID
> and 2) inner not outer

Looks fine

> 
>     Jim> should refer to the "token ID" rather than the "outer token
>     Jim> type" either that or the item in the table should be updated.
> 
>     Jim> section 5.2 refers to "token type" - I think that maybe this is
>     Jim> the most constant phrase to be used.
> 
> I've updated the registry to talk about token type identifiers.
> 
>     Jim> I will say that this version did harmonize and make the token
>     Jim> naming scheme much more consistent and readable.  I think this
>     Jim> is a big improvement.
> Great!
> 
>     Jim> s/secondsubtoken/second subtoken/ (in the table)
> 
>     Jim> Section 5.3 - Is there going to be a rule that you should send
>     Jim> two error subtokens in the even t\the length is greater than 8?
>     Jim> I can understand saying you should ignore the extended bytes
>     Jim> but should you really ignore the error code itself?
> 
> In 04 we have initiators MUST ignore octets beyond the GSS EAP error code
> for future extensibility.  Thanks for the catch.
> 
>     Jim> Section 5.4 - you have different names for the acceptor name
>     Jim> subtokens in the description of what is permitted and the
>     Jim> actual subtoken names - I think you might want to harmonize
>     Jim> this.
> 
>     Jim> Is there a rason that the EAP request subtoken is not
>     Jim> documented in section 5.4 since it is a required subtoken from
>     Jim> in the Initial State message from the acceptor?
> 
> I've added a reference. However I think it's better to document EAP
request
> and response near each other.
> Note that if we adopt the proposal to reduce a round trip this subtoken
goes
> away from initial state.
> 
>     Jim> Section 5.4.1 - I realize this is a debugging string (Vender
>     Jim> Subtoken) but is there any reason in this day and age not make
>     Jim> it a UTF8 string?  (Other than it is not one for Kerbros)
> 
> It doesn't exist for Kerberos (which has no vendor string I'm aware of) so
I
> don't think that's a concern.
> 
> I've made it UTF-8; I don't care.
> 
>     Jim> Section 5.4.3 - Should something be said about what the
>     Jim> acceptor should do if the initiator sends an acceptor name
>     Jim> which is not completely correct for the specific acceptor.  I
>     Jim> am thinking specifically of things like adding a host name or
>     Jim> adding some service specifics to the acceptor name.  Is this
>     Jim> permitted?  Or is this and error condition or since this is
>     Jim> typically not sent is the acceptor name from the client to be
>     Jim> used in all events. (unless totally wrong)
> 
> I think you mean 5.4.2 not 5.4.3?
> My assumption is that you need to send a superset of what the acceptor
> expects, else things will fail at channel binding. I think you want to
leave it to
> channel binding to fail unless an IDP wants to implement  some form of
> aliasing.

In 5.4.2 s/hosntame/hostname/

I meant 5.4.3 - because I was assuming this was an Acceptor error rather
than an Initiator.  That is if the Acceptor name is not a superset then it
would return an error.  The question is should you both error and return the
response in some sense.  

One possibility is that the Initiator sends name #1, the Acceptor replies
with name #2 and then the intiator says that this is acceptable and sends
name #2 as part of the channel binding.    In this case the was no error but
the initator name is not a superset of the acceptor name that came back.

> 
> 
> 
>     Jim> para #2 s/this token/This token/
> 
>     Jim> Section 5.5 s/ACCEPTOR/acceptor/

Not fixed

> 
>     Jim> The first bullet of this section is causing me some mental
>     Jim> problems.  The acceptor cannot confirm that the protected
>     Jim> result and the final result are consistent - this is hidden
>     Jim> from the acceptor.  --- or you need to be passing the protected
>     Jim> result as a RADIUS attribute, at which point it is not really
>     Jim> protected anymore.
> 
> For combined authenticators the acceptor can and should evaluate the
> protected result.
> For pass-through authenticators the acceptor should confirm there's AAA
> success if there is EAP success.

Ok - I think this is more clear now.

> 
>     Jim> The acceptor can confirm that a key has been delivered to it,
>     Jim> but it does not know the source of the key - i.e. was it
>     Jim> derived or just transmitted inside of the EAP session.
> 
> Here, we mean the security claim discussed in section 7.10 of RFC 3748,
which
> probably includes transmitting a key.
> Their term, not mine.
> I've added a reference.
> 
Ok

> 
> 
>     Jim> Should the acceptor or the initiator send the error subtoken -
>     Jim> or should the acceptor be looking for clear EAP messages and
>     Jim> generate a failure?
> 
> I don't understand.
> 
>     Jim> I think you need to carefully re-read the section and verify
>     Jim> that you think it is correct.
> 
> I think it is consistent with what EAP does and what our implementation
> does.
> There are some disadvantages to how EAP handles failures.
> We can discuss at IETF 82 if you like.

I think this would probably be a good idea - just so I can be sure that we
understand each other and what the doc says.  
> 
>     Jim> Setion 5.6 - Please tell me which type of channel binding I am
>     Jim> getting at this point. (I know it is GSS-API channel binding,
>     Jim> but given that two different types are discussed in the
>     Jim> document I think being explcit would be good.)
> 
> Also added a forward reference.
> 
>     Jim> Section 6 - Is the KMSK in the "Tn = " line supposed to be
>     Jim> GMSK?
> Yes.
> 
> 
>     Jim> Section 6.1 - I am unclear what the extension option field is
>     Jim> referring to please clarify.
> 
> This was all wrong and has been fixed. Thanks for the reality check.


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