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

[Alexander Bokovoy]

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.
-- 
/ Alexander Bokovoy