Amavis - DKIM sign 256 or 1024 bits?

[Jernej Porenta]

Just for info: 

This morning MAAWG published recommendations on keeping DKIM keys secure:
http://www.maawg.org/sites/maawg/files/news/M3AAWG_Key_Implementation_BP-2012-11.pdf

cheers, Jernej



On Nov 5, 2012, at 3:38 PM, Patrick Ben Koetter <p at sys4.de> wrote:

> * gedir.goncalves at bndes.gov.br <gedir.goncalves at bndes.gov.br>:
>> Hi, good morning.
>> 
>> I would like to take a doubt with colleagues from the list. 
>> 
>> I installed and I enabled Amavis 2.6.6 in environmet of the test, I 
>> created DKIM Key 1024 bit and sign is working properly. But I have a 
>> doubts, when I see the message header I see that the signature is recorded 
>> 256.
> 
> amavis creates 1024 bit size keys be default. You can override that and use
> less that 512, but no less or up to 4096, but not more:
> 
>    $nbits = 1024  if !defined($nbits) || $nbits eq '';
>    $nbits =~ /^\d+\z/  or die "Number of bits in a key must be numeric\n";
>    $nbits >=  512  or die "Number of bits too small (suggested 768..1536)\n";
>    $nbits <= 4096  or die "Number of bits too large (suggested 768..1536)\n";
>    defined $fname && $fname ne '' or die "File name for a key not provided\n";
> 
> 
> p at rick
> 
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