[Freeipa-devel] Kerberos over HTTPS (KDC proxy)

[Martin Kosek]

On 05/28/2015 11:12 AM, Alexander Bokovoy wrote:
> On Thu, 28 May 2015, Petr Spacek wrote:
>> On 28.5.2015 07:42, Jan Cholasta wrote:
>>> Dne 27.5.2015 v 15:54 Simo Sorce napsal(a):
>>>> On Wed, 2015-05-27 at 15:47 +0200, Jan Cholasta wrote:
>>>>> Dne 27.5.2015 v 15:43 Simo Sorce napsal(a):
>>>>>> On Wed, 2015-05-27 at 13:57 +0200, Jan Cholasta wrote:
>>>>>>>>>
>>>>>>>>>      ipa config-mod --enable-kdcproxy=TRUE
>>>>>>>>>      ipa config-mod --enable-kdcproxy=FALSE
>>>>>>>
>>>>>>> I don't like this approach, as it is completely inconsistent with
>>>>>>> every
>>>>>>> other optional component. There should be *one* way to handle them
>>>>>>> and
>>>>>>> there already is one, no need to reinvent the wheel.
>>>>>>
>>>>>> Sorry Jan, but this is really the correct approach.
>>>>>
>>>>> I don't think so.
>>>>>
>>>>>>
>>>>>> We want a boolean in LDAP to control whether the IPA Domain allows
>>>>>> proxying or not, the code is embedded in the overall framework and has
>>>>>> no need for explicit install/uninstall unlike the CA or DNS components.
>>>>>
>>>>> There is a boolean for every other component/service as well. If you
>>>>> want to add new API to manipulate the boolean, fine, but it should be
>>>>> done in a generic way that works for other components as well.
>>>>
>>>> This is the same as:
>>>> ipa config-mod --enable-migration=TRUE
>>>>
>>>> Why is it a problem ?
>>>
>>> This is a switch to enable the migrate-ds plugin. I think it's hardly fair to
>>> compare it to a whole new component which provides a new service to the
>>> outside world.
>>>
>>>> This is not a separate service.
>>>
>>> How is it not a separate service? If it's installed, MS-KKDCP is provided to
>>> the outside world, and if it's not installed MS-KKDCP is not provided to the
>>> outside world. How is this different from, say, DNS? (Besides implementation
>>> details, such as what protocols or how many daemons it uses - think about IPA
>>> as a black box for a moment.)
>>
>> I very much agree with Honza - we have per-replica boolean for every service
>> so there is no reason not to have one for kdc proxy, especially when we
>> consider future containerization of services.
> A mere 'me too' here. Note that once updates to RFC 4120 as outlined in
> https://tools.ietf.org/html/draft-mccallum-kitten-krb-service-discovery-00
> would be accepted, clients will not be assuming all of replicas serve
> MS-KKDCP proxies so there will not be need to run them everywhere.
> Rather, only the servers on a network boundary will need to be
> advertised. This means we'll eventually get per-replica need as well.
> 
> It is fine to assume right now that all of them are going to run
> MS-KKDCP proxy but configuration isn't really going to be global.
> 
> Additionally, ipa-kdcproxy-manage would need to manipulate
> _kerberos.$DOMAIN URI DNS records too, so there is more than just
> switching the boolean here.

I see. My question is - if we go this way, what is then the reasonable subset
configuration functionality realistic for FreeIPA 4.2 GA? (As we want this
feature in for 4.2). Is ipa-kdcproxy-manage doable?

What is the proposed API here?

ipa-kdcproxy-manage list
ipa-kdcproxy-manage enable <server>
ipa-kdcproxy-manage disable <server>

?