[Freeipa-devel] [PATCHES] 94-99 Read and use per-service PAC type

Fri Mar 8 09:50:46 UTC 2013

On 03/07/2013 06:32 PM, Sumit Bose wrote:
> On Wed, Mar 06, 2013 at 05:33:43PM +0100, Sumit Bose wrote:
>> On Wed, Mar 06, 2013 at 08:51:47AM -0500, Simo Sorce wrote:
>>> On Wed, 2013-03-06 at 14:49 +0100, Martin Kosek wrote:
>>>> On 03/06/2013 10:41 AM, Sumit Bose wrote:
>>>>> On Tue, Mar 05, 2013 at 05:13:58PM +0100, Martin Kosek wrote:
>>>>>> On 03/04/2013 04:22 PM, Sumit Bose wrote:
>>>>>>> On Fri, Mar 01, 2013 at 08:58:34AM -0500, Simo Sorce wrote:
>>>>>>>> On Fri, 2013-03-01 at 10:08 +0100, Martin Kosek wrote:
>>>>>>>>> On 03/01/2013 09:20 AM, Sumit Bose wrote:
>>>>>>>>>> On Fri, Mar 01, 2013 at 08:33:51AM +0100, Martin Kosek wrote:
>>>>>>>>>>> On 02/28/2013 03:28 PM, Simo Sorce wrote:
>>>>>>>>>>>> On Thu, 2013-02-28 at 13:02 +0100, Martin Kosek wrote:
>>>>>>>>>>>>> On 02/28/2013 12:42 PM, Sumit Bose wrote:
>>>>>>>>>>>>>> On Thu, Feb 28, 2013 at 08:44:35AM +0100, Martin Kosek wrote:
>>>>>>>>>>>>>>> On 02/27/2013 06:48 PM, Sumit Bose wrote:
>>>>>>>>>>>>
>>>>>>>>>>>>>>> Hi Sumit,
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> This looks like a good idea and would prevent the magic default PAC type, yes.
>>>>>>>>>>>>>>> Though I would not add this service-specific setting to global IPA config object.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> I would rather like to see that in the service tree, for example as a
>>>>>>>>>>>>>>> configuration option of the service root which could be controlled with
>>>>>>>>>>>>>>> serviceconfig-* commands (we already have dnsconfig, trustconfig), e.g:
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> # ipa serviceconfig-add-pacmap --service=nfs --pac-type=NONE
>>>>>>>>>>>>>>> # ipa serviceconfig-add-pacmap --service=cifs --pac-type=PAD
>>>>>>>>>>>>>>> # ipa serviceconfig-show
>>>>>>>>>>>>>>>    Default PAC Map: nfs:NONE, cifs:PAD
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Are you thinking of having this in addition to the for-all-services
>>>>>>>>>>>>>> default values in cn=ipaConfig,cn=etc or shall those be dropped? I don't
>>>>>>>>>>>>>> like the first case because then three different objects needs to be
>>>>>>>>>>>>>> consulted to find out which is the right type. This wouldn't be an issue
>>>>>>>>>>>>>> for the plugin, but I think it is hard for the user/admin to follow.
>>>>>>>>>>>>>
>>>>>>>>>>>>> Hm, you are right.
>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> If the current defaults shall be dropped I think this is a major change
>>>>>>>>>>>>>> because it will require changes in the current CLI and WebUI which will
>>>>>>>>>>>>>> be visible to the users. I'm not against this change, I'm just wondering
>>>>>>>>>>>>>> if it is worth the effort for the next release?
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Maybe an argument to keep this is in global default is that the settings
>>>>>>>>>>>>>> are used for the host/*.* services as well which are in a different
>>>>>>>>>>>>>> sub-tree of the cn=accounts container. Additionally in future we might
>>>>>>>>>>>>>> want apply those setting to the user TGTs as well?
>>>>>>>>>>>>>
>>>>>>>>>>>>> Yeah, that was actually my point. That we are mixing service-specific PAC
>>>>>>>>>>>>> "rules" to the global setting. Which may be shared with host/*.* principals and
>>>>>>>>>>>>> user principals. This automatic PAC rules may require some designing so that is
>>>>>>>>>>>>> is generally usable.
>>>>>>>>>>>>
>>>>>>>>>>>> I think putting everything in the general config is more understandable
>>>>>>>>>>>> and discoverable. These per-service defaults are basically exceptions to
>>>>>>>>>>>> the general rule so it make sense to keep everything together.
>>>>>>>>>>>>
>>>>>>>>>>>> Simo.
>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Ok, if these are really just an exceptions to the general rule (and there will
>>>>>>>>>>> not be too many of them), I think we can leave it in config entry. But if we
>>>>>>>>>>> expect to have exceptions for other types of entries (hosts, users), I think we
>>>>>>>>>>> should rather use something like "service:nfs:NONE" do distinguish this exception.
>>>>>>>>>>>
>>>>>>>>>>> Question is, do we want to implement the interface and processing for that in
>>>>>>>>>>> current Sumit's patches or do we use that is they are?
>>>>>>>>>>
>>>>>>>>>> I would like to update the patches so that they can handle the
>>>>>>>>>> service:TYPE style entry and replace the current update code with just
>>>>>>>>>> adding nfs:NONE to the global options. I will update the design page
>>>>>>>>>> accordingly, too.
>>>>>>>>>
>>>>>>>>> Ok. If the update procedure shrinks just to adding service:nfs:NONE then it'd
>>>>>>>>> be great.
>>>>>>>>
>>>>>>>> If we need to distinguish between service principals and user principals
>>>>>>>> I would prefer rather use a special keyword for upns
>>>>>>>>
>>>>>>>> service: is redundant and I do not want here to be able to say
>>>>>>>> upn:martin:NONE because per principal options are available on the
>>>>>>>> principal object.
>>>>>>>>
>>>>>>>> I actually really do not see the need for changing the default just for
>>>>>>>> user principals. If we are worried that one day we might want to really
>>>>>>>> have upn:NONE, then let's use nfs/:NONE, host/:NONE etc... so one day we
>>>>>>>> might add upn:NONE and the lack of / will tell us this is not a service
>>>>>>>> named upn/foo.bar.baz but rather it means user principal names.
>>>>>>>>
>>>>>>>> However I do not see us ever really needing upn:NONE
>>>>>>>>
>>>>>>>>>> I would prefer if the enhancements needed for the CLI and WebUI can be
>>>>>>>>>> covered by other/new tickets, but I'm happy to add the needed
>>>>>>>>>> information to the design page too.
>>>>>>>>>>
>>>>>>>>>> bye,
>>>>>>>>>> Sumit
>>>>>>>>>
>>>>>>>>> I am OK with adding the interface for this special exception later. In that
>>>>>>>>> case, a ticket + note in the design as you mentioned would be enough.
>>>>>>>>
>>>>>>>> Ack.
>>>>>>>>
>>>>>>>> Simo.
>>>>>>>>
>>>>>>>
>>>>>>> Please find attached a new version of the patches. 0095 i(updating) is
>>>>>>> renamed and much simpler now. I opened
>>>>>>> https://fedorahosted.org/freeipa/ticket/3484 to added the needed change
>>>>>>> for 'service:TYPE' to CLI and WebUI. For the time being I've added
>>>>>>> patch 0108 which simply allows 'nfs:NONE' as a type to make sure that it
>>>>>>> is not deleted accidentally when e.g. using the WebUI. If you do not
>>>>>>> like it it can simply be dropped, everything is working fine without it.
>>>>>>>
>>>>>>> bye,
>>>>>>> Sumit
>>>>>>>
>>>>>>
>>>>>> Patch 0098:
>>>>>>
>>>>>> If this part does not match (and it will not for all non-nfs service principals):
>>>>>>
>>>>>> +            if (service_type->length == (sep - authz_data_list[c]) &&
>>>>>> +                strncmp(authz_data_list[c], service_type->data,
>>>>>> +                        service_type->length) == 0) {
>>>>>> +                authz_data_type = sep + 1;
>>>>>> +            }
>>>>>>
>>>>>> krb5kdc.log will contain an error:
>>>>>>
>>>>>> Mar 05 10:48:50 ipa.linux.ad.test krb5kdc[26703](Error): Ignoring unsupported
>>>>>> authorization data type [nfs:NONE].
>>>>>> Mar 05 10:48:50 ipa.linux.ad.test krb5kdc[26703](info): TGS_REQ (4 etypes {18
>>>>>> 17 16 23}) 10.16.78.33: ISSUE: authtime 1362482261, etypes {rep=18 tkt=18
>>>>>> ses=18}, HTTP/ipa.linux.ad.test at LINUX.AD.TEST for
>>>>>> ldap/ipa.linux.ad.test at LINUX.AD.TEST
>>>>>>
>>>>>> I think we should just "continue" in this case.
>>>>>
>>>>> good catch, fixed
>>>>
>>>> Ok, thanks.
>>>>
>>>>>
>>>>>>
>>>>>> Otherwise, this looks and works fine.
>>>>>
>>>>> Thank you for the review, new version attached.
>>>>>
>>>>> I have an additional question about processing the service specific
>>>>> defaults. Using 'service:NONE' is unambiguous because NONE trumps all.
>>>>> But what do we expect if e.g. the defaults are MS-PAC and ldap:PAD for a
>>>>> LDAP service ticket. Shall it contain PAC and PAD or only a PAD? I think
>>>>> the first one where all defaults which apply to a service are added up
>>>>> is more clear, and this is also the way the current code works. But I
>>>>> wouldn't mind to change the logic if you think it makes more sense the
>>>>> other way round, i.e. if there is a service specific default matching
>>>>> the requested service only the service specific default are accounted.
>>>>
>>>> Hmm, that's a good question. I understand service:PACTYPE as an exclusion to
>>>> the general setting, so for me it would make sense to override the global
>>>> config - i.e. tje second case.
>>>>
>>>> Thus, if global config is MS-PAC, ldap:PAD, I think that ldap should have just
>>>> PAD. If one also want MS-PAC, it should be set like "MS-PAC, ldap:PAD,
>>>> ldap:MS-PAC". Otherwise you would not be able to configure that you want MS-PAC
>>>> for all services and _only_ PAD for ldap...
>>>>
>>>> Does it make sense? We should also make sure that we update the RFE page to
>>>> whatever we decide to do.
>>>
>>> +1 to Martin's choice.
>>
>> Martin, Simo, thank you for the feedback. I will send an new version of
>> the patches, add a section in the design page explaining the details and
>> add some tests for this logic.
>>
>> bye,
>> Sumit
>
> Design pages is updated and new patches attached.
>
> bye,
> Sumit
>

Thanks, this works great. I just updated the commit messages and added a link 
to the ticket.

ACK. Pushed to master.

Martin