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

[Rob Crittenden]

Martin Kosek wrote:
> On 09/17/2012 09:35 PM, Rob Crittenden wrote:
>> 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
>>
>
> One more test should not hurt. Updated patch attached.
>
> Martin
>

ACK