Hi Fabio,

I went through the last version of the document.

I still think that in a few place SHOULD should be replaced by MUST. But it is 
just  my point of view. You can leave SHOULD.

There are just few residual issues:

- Introduction: The second sentence is not coherent with the first one. The 
concept of EID-to-RLOC mappings as not been introduced so starting the sentence 
with “These EID-to-RLOC mapping s…” is pretty unclear. I would suggest you add 
another sentence.

- Section 7 IANA Considerations: For almost all of the registries the value “0” 
has a special meaning that this demo is defining, hence the “defined in” field 
should state “this memo”

- - Section 7 IANA Considerations: The section is not yet 5226 compliant. More 
specifically, you have to state for each registry how new values are allocated 
(e.g. FCFS, expert review, etc..)


Check again the nits:

 Checking nits according to http://www.ietf.org/id-info/checklist :
  ----------------------------------------------------------------------------

  == There are 10 instances of lines with non-RFC6890-compliant IPv4
     addresses in the document.  If these are example addresses, they should
     be changed.

  Checking references for intended status: Experimental
  ----------------------------------------------------------------------------

  == Missing Reference: 'RFC4634' is mentioned on line 840, but not defined

  ** Obsolete undefined reference: RFC 4634 (Obsoleted by RFC 6234)


The above nits reminds me of another issue that the IESG will certainly raise: 
can we have all the examples in IPv6 only?
The latest directives are that either you use both v4 and v6 or v6-only, but 
NOT v4-only.

Thanks

ciao

L.




> On 27 Oct 2016, at 23:48, Fabio Maino <[email protected]> wrote:
> 
> Luigi, 
> I agree with all the comments. 
> 
> The document attached should reflect all your suggestions. 
> 
> A few notes below, just to explicitly ack the changes you suggested. 
> 
> 
> On 10/26/16 2:13 AM, Luigi Iannone wrote:
>> Hi Fabio,
>> 
>> Yes we are converging, very few points are left. 
>> 
>> Inline are my comments, I snipped everything that we already agreed up on.
>> 
>> L.
>> 
>>> On 26 Oct 2016, at 02:14, Fabio Maino <[email protected] 
>>> <mailto:[email protected]>> wrote:
>>> 
>> 
>> [snip]
>> 
>> 
>>> 
>>>> 
>>>> Also, what is the MS stubbornly insists in using an algorithm that the ITR 
>>>> does not support?
>>> 
>>> The MS might not have alternatives, as it might only support one algorithm. 
>>> 
>> 
>> Sure
>> 
>> The question is: can we have situations in which MS replies always with the 
>> same algorithm (because has no alternatives) and the ITR is never able to 
>> understand that reply (because has no alternatives).
>> 
>> From my understanding this can happen, right? 
>> 
>> LISP-SEC has no way to prevent it, right?
>> 
>> What is needed is a policy like “ITR tries using all of the algorithm it 
>> supports and then gives up”, right?
>> 
>> If the answer to those questions is yes, then IMO this should be spelled out 
>> somewhere.
>> 
>> 
> 
> got it. Agreed. 
> 
> 
>>> 
>>> 
>> [snip]
>> 
>>>> 
>>>>> 
>>>>>> 
>>>>>>>    The KDF ID field, specifies the suggested key derivation function to
>>>>>>>    be used by the Map-Server to derive the MS-OTK.
>>>>>> 
>>>>>> What happens if the MS will choose a KDF ID not supported by the ITR?
>>>>>> Can you clarify how to solve this situation or explain why this will 
>>>>>> never happen?
>>>>> 
>>>>> This is described a few paragraphs below: 
>>>>> "
>>>>> If the KDF ID in the Map-Reply does not match the
>>>>>    KDF ID requested in the Map-Request, the ITR SHOULD discard the Map-
>>>>>    Reply and send, at the first opportunity it needs to, a new Map-
>>>>>    Request with a different KDF ID, according to ITR's... 
>>>>> "
>>>>> 
>>>> 
>>>> This does not guarantee that the MS will reply with something the ITR 
>>>> understands….
>>> 
>>> For some local ITR's policy it may not be guaranteed. It's a balance 
>>> between reachability and security that the ITR will have to choose. 
>>> 
>>> 
>> I am not sure I understand your reply.
>> 
>> My point was the same as above: what if MS and ITR are not able to talk?
> 
> ok. So this is addressed by the same fix used for the previous comment. I'll 
> specify that the ITR will stop re-sending map-requests once all HMAC IDs 
> supported by the ITR have been attempted. 
>  
>> 
>> 
>>> 
>>> 
>>> 
>>> 
>>>> 
>>>> 
>>>> 
>>>>>> 
>>>>>>>    The EID-AD length is set to 4 bytes, since the Authentication Data
>>>>>>>    does not contain EID-prefix Authentication Data, and the EID-AD
>>>>>>>    contains only the KDF ID field.
>>>>>>> 
>>>>>>>    In response to an encapsulated Map-Request that has the S-bit set, an
>>>>>>>    ITR MUST receive a Map-Reply with the S-bit set, that includes an
>>>>>>>    EID-AD and a PKT-AD.  If the Map-Reply does not include both ADs, the
>>>>>>>    ITR MUST discard it.  In response to an encapsulated Map-Request with
>>>>>>>    S-bit set to 0, the ITR expects a Map-Reply with S-bit set to 0, and
>>>>>>>    the ITR SHOULD discard the Map-Reply if the S-bit is set.
>>>>>> Why a “SHOULD”? If the Map-Request has S-bit=0 it mean that there is no 
>>>>>> AD, hence no OTK, how can the ITR decrypt the reply?????
>>>>>> It MUST discard…..
>>>>> 
>>>>> If S-bit = 0 there's no Authentication Data. The Map-reply is in clear, 
>>>>> and can be read.
>>>> 
>>>> I am not sure you understood my point.
>>>> 
>>>> You send a Map-Request with S=0, hence unenbcrypted. How can you possible 
>>>> receive a Map-Reply with S=1?
>>>> How is it encrypted if the ITR did not provide any OTK?
>>> 
>>> Misconfiguration, bugs? I was just trying to enumerate the behaviors of the 
>>> ITR. There's probably something wrong, and the map-reply should be 
>>> discarded. Still the mapping is readable, so an ITR favoring reachability 
>>> may decide to use the mapping. 
>>> 
>> 
>> Oh… I may see the misunderstanding. You are saying that the bit is set in 
>> the Map-Reply, but actually the content is not encrypted, right? SO the ITR 
>> can decide whether or not to use it.
>> 
>> Is that right?
> 
> right. 
> 
>> 
>> 
>> [snip]
>>>>>> I think “log message" is too much implementation specific. 
>>>>>> If there is a notification, and how this notification is done, is 
>>>>>> implementation specific IMHO.
>>>>> ok. Same as above.
>>>>>> 
>>>>>>>    The EID-record with EID-prefix 1.1.2.0/24 is stored in the map-cache
>>>>>>>    because it matches the second EID-prefix contained in the EID-AD.
>>>>>>> 
>>>>>>>    The EID-record with EID-prefix 1.2.0.0/16 is not processed since it
>>>>>>>    is not included in any of the EID-ADs signed by the Map-Server.  A
>>>>>>>    log message is issued.
>>>>>> I think “log message" is too much implementation specific. 
>>>>>> If there is a notification, and how this notification is done, is 
>>>>>> implementation specific IMHO.
>>>>> ok. Same as above
>>>>>> 
>>>>>>>   In this last example the ETR is trying to
>>>>>>>    over claim the EID-prefix 1.2.0.0/16, but the Map-Server authorized
>>>>>>>    only 1.2.3.0/24, hence the EID-record is discarded.
>>>>>> Reading the example I am not sure I would follow this behaviour.
>>>>>> Only 1 record out of 3 is valid so why should I actually trust the ETR 
>>>>>> instead of throwing everything away?
>>>>>> Can you explain ???
>>>>> The other two records are validated by the MS, so there is no reason to 
>>>>> throw those away.
>>>> 
>>>> Yes, but the ETR is still trying to cheat on the third one….
>>>> So the ETR may be compromised, why should I send traffic to him???
>>> 
>>> ITR has flagged the security exception with the log entry, and some local 
>>> ITR policy will decide what to do (including stop encapsulating to the ETR, 
>>> if that's what is specified by the policy).  At the LISP level LISP-SEC has 
>>> done its job: verified mapping  goes into the map-cache, overclaimed 
>>> mapping is dropped. 
>>> 
>> 
>> This is not what the above text states. The text states that the valid 
>> EID-record is stored in the map-cache.
>> To be consistent with your reply you should change and state that the 
>> EID-record is eligible to be used by the ITR.
> 
> 
> got it. I changed 'stored into the map-cache' with 'eligible to be used by 
> the ITR'. For consistency I have used similar language for the other two 
> cases (rather than not processed).  
> 
>> 
>> BTW to be consistent with other LISP document you should use "LISP Cache” 
>> instead of “map-cache” (in the whole document).
>> 
>> 
> ok. With the change above we don't use the word map-cache anymore in the 
> document. So this is addresses as well.
> 
> Thanks!
> Fabio
> 
> 
> 
>> [snip]
>> 
> 
> <Diff_ draft-ietf-lisp-sec-11.txt - 
> draft-ietf-lisp-sec-12b.txt.html><draft-ietf-lisp-sec-12b.txt>

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