[Freeipa-devel] [PATCH] 302 Stricter IP network validator in dnszone-add command

[Rob Crittenden]

Martin Kosek wrote:
> On 09/05/2012 01:02 PM, Jan Cholasta wrote:
>> Dne 5.9.2012 12:48, Martin Kosek napsal(a):
>>> On 09/05/2012 12:36 PM, Jan Cholasta wrote:
>>>> Dne 5.9.2012 12:22, Petr Spacek napsal(a):
>>>>> On 09/05/2012 11:30 AM, Jan Cholasta wrote:
>>>>>> Dne 5.9.2012 10:04, Martin Kosek napsal(a):
>>>>>>> We allowed IP addresses without network specification which lead
>>>>>>> to unexpected results when the zone was being created. We should rather
>>>>>>> strictly require the prefix/netmask specifying the IP network that
>>>>>>> the reverse zone should be created for. This is already done in
>>>>>>> Web UI.
>>>>>>>
>>>>>>> A unit test exercising this new validation was added.
>>>>>>>
>>>>>>> https://fedorahosted.org/freeipa/ticket/2461
>>>>>>>
>>>>>>
>>>>>> I don't like this much. I would suggest using CheckedIPAddress and not
>>>>>> forcing
>>>>>> the user to enter the prefix length instead.
>>>>>>
>>>>>> CheckedIPAddress uses a sensible default prefix length if one is not
>>>>>> specified
>>>>>> (class-based for IPv4, /64 for IPv6) as opposed to IPNetwork (/32 for
>>>>>> IPv4,
>>>>>> /128 for IPv6 - this causes the erroneous reverse zones to be created as
>>>>>> described in the ticket).
>>>>>>
>>>>> Hello,
>>>>>
>>>>> I don't like automatic netmask guessing. I have met class-based guessing
>>>>> in Windows (XP?) and I was forced to overwrite default mask all the time
>>>>> ...
>>>>
>>>> If there was no guessing, you would have to write the netmask anyway, so I
>>>> don't see any harm in guessing here.
>>>>
>>>>>
>>>>> IMHO there is no "sensible default prefix" in real world. I sitting on
>>>>> network with /23 prefix right now. Also, I have never seen 10.x network
>>>>> with /8 prefix.
>>>>>
>>>>
>>>> While this might be true for IPv4 in some cases, /64 is perfectly sensible for
>>>> IPv6. Also, I have never seen 192.168.x.x network with non-/24 prefix.
>>>>
>>>> Honza
>>>>
>>>
>>> While this may be true for 192.168.x.x, it does not apply for 10.x.x.x networks
>>> as Petr already pointed out. I don't think that there will be many people
>>> expecting that a reverse zone of 10.0.0.0/24 would be created.
>>
>> And they would be correct, because the default prefix length for a class A
>> network is /8, not /24.
>>
>>>
>>> And since FreeIPA is mainly deployed to internal networks, I assume this will
>>> be the case of most users.
>>>
>>> Martin
>>>
>>
>> OK, but what about IPv6? Correct me if I'm wrong, but the prefix length is
>> going to be /64 99% of the time for IPv6.
>>
>> The installer uses /24 for IPv4 addresses and /64 for IPv6 addresses, maybe
>> this should be used as a default here as well.
>>
>> Honza
>>
>
> In the end, I choose a more liberal approach and instead of defining a more
> stricter validator for IPv4 only I rather used approach already implemented in
> the installers, i.e. default length of network prefix is 24 for IPv4 and 64 for
> IPv6.
>
> Updated patch attached.
>
> Martin

Works for me. I wonder if this is a candidate for some more unit tests...

rob