Hello, Ran,

Apologies for the delay in my response...

On 07/06/2018 07:57 PM, R. Atkinson wrote:
> 
> 
>> On Jul 6, 2018, at 12:24, Fernando Gont <[email protected]> wrote:
>> It does. :-) (agreed on making the knob available)
>>
>> Regarding the advice, I'm wondering what would be the recommended advice
>> for transit routers.  I guess it would be "drop, unless it's a MLS
>> network", with the operator applying this configuration (and hence
>> knowing what's the context in which this device s operating)
> 
> Fernando,
> 
> I don’t think "transit router true/false” is the variable that would determine
> whether to drop CALIPSO packets or not.  Instead, it is “MLS enabled 
> true/false” that would determine whether to drop.

Point taken. (A side question, for my own personal interest: If you have
an MLS environment, wouldn't it be your bet that transit drops your
packets -- i.e., they are *transit*)




> I am open to word-smithing/editing, but here is some candidate revised 
> replacement text for 4.3.9.5 based on today’s email:
> 
>   "Recommendations for handling the CALIPSO option depend  on the 
>    deployment environment, rather than whether an intermediate system 
>    happens to be deployed as a transit device (e.g., IPv6 transit router)."
> 
>    “Explicit configuration is the only method via which an intermediate system
>   can know whether or not that particular intermediate system has been 
>   deployed within a Multi-Level Secure (MLS) environment.  In many cases, 
>   ordinary commercial intermediate systems (e.g.,  IPv6 routers & firewalls) 
>   are the majority of the deployed intermediate systems inside an MLS 
>   network environment.  
> 
>  “For Intermediate systems that DO NOT implement RFC-5570, there 
>   SHOULD be a configuration option to EITHER (a) drop packets containing 
>   the CALIPSO option OR  (b) to ignore the presence of the CALIPSO option
>   and forward the packets normally.  In non-MLS environments, such
>   intermediate systems SHOULD have this configuration option set to (a)
>   above.  In MLS environments, such intermediate systems SHOULD
>   have this option set to (b) above.  The default setting for this 
> configuration
>   option SHOULD be set to (a) above, because MLS environments are much
>   less common than non-MLS environments."
> 
>   “For Intermediate systems that DO implement RFC-5570, there SHOULD 
>   be configuration options (a) and (b) from the preceding paragraph and 
>   also a third configuration option (c) to process packets containing
>   a CALIPSO option as per RFC-5570.  When deployed in non-MLS
>   environments, such intermediate systems SHOULD have this configuration
>   option set to (a) above.  When deployed in MLS environments, such
>   intermediate systems SHOULD have this set to (c).  The default setting
>   for this configuration option MAY be set to (a) above, because MLS 
>   environments are much less common than non-MLS environments."

The text looks great, and I will incorporate it in the next rev- If any
folks have any objections please do let us know.

Thanks so much, Ran!

Cheers,
-- 
Fernando Gont
e-mail: [email protected] || [email protected]
PGP Fingerprint: 7809 84F5 322E 45C7 F1C9 3945 96EE A9EF D076 FFF1



_______________________________________________
OPSEC mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/opsec

Reply via email to