Re: [PATCH] resolv: set edns max buffer size to 1232

[Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>]

On 11/04/23 10:43, Cristian Rodríguez via Libc-alpha wrote:
> ping? should not be a controversial thing to do. Most software out there
> already does.
> 

LGTM, although I am not really sure about the implications of this change.
The links you provided does say it is a conservative change thou.

> 
> On Wed, Apr 5, 2023 at 9:21 PM Cristian Rodríguez <crrodriguez@opensuse.org>
> wrote:
> 
>> Year 2020, Large scale DNS operators and software vendors
>> agreed to set the maximum edns buffer size to 1232.
>>
>> BIND9(1), NSD(2), unbound (3), dnsmasq etc  currently use this as
>> default, libc resolver should too.
>>
>> 1.
>> https://downloads.isc.org/isc/bind9/9.16.8/doc/arm/html/notes.html#feature-changes
>> 2. https://www.nlnetlabs.nl/news/2020/Oct/08/nsd-4.3.3-released/
>> 3. https://www.nlnetlabs.nl/news/2020/Oct/08/unbound-1.12.0-released/
>>
>> Signed-off-by: Cristian Rodríguez <crrodriguez@opensuse.org>
>> ---
>>  resolv/resolv-internal.h | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/resolv/resolv-internal.h b/resolv/resolv-internal.h
>> index c55f3c0366..c79d5f2135 100644
>> --- a/resolv/resolv-internal.h
>> +++ b/resolv/resolv-internal.h
>> @@ -67,7 +67,7 @@ enum
>>         spoofing attacks because the randomness in a DNS packet is
>>         concentrated in the first fragment (with the headers) and does
>>         not protect subsequent fragments.  */
>> -    RESOLV_EDNS_BUFFER_SIZE = 1200,
>> +    RESOLV_EDNS_BUFFER_SIZE = 1232,
>>    };
>>
>>  struct resolv_context;
>> --
>> 2.40.0
>>