Re: OT: DNS restrictions for a mail server

[mouss <mo...@netoyen.net>]

Daniel J McDonald wrote:
> On Wed, 2008-10-22 at 23:59 +0200, Jonas Eckerman wrote:
>> Matus UHLAR - fantomas wrote:
>>
>>>> In my understanding, these are different concepts. In particular, RMX
>>>> doesn't hijack the TXT record, which is one of the major sins of SPF.
>>> Yes, but they both were designed to do the same work. SPF however can do
>>> more. TXT was used because nothing else could, at least I think so.
>> They could have used a prefix "host" to avoid hijacking the main 
>> TXT record. (So you'd query the TXT record for 
>> "__spf__.domain.tld" or something like that instead of the TXT 
>> record for "domain.tld" when checking SPF.
> 
> Could of, but underscores are not a legal character in domain names.

no, they are perfectly legal "in domain names". They are being used in 
DKIM. don't confuse with hostnames.

> 
> And now BIND 9.4 supports the SPF RR type, so we just have to wait a
> decade or two until everyone still running bind 4.0 has a chance to
> upgrade.... ;-)
> 

and a century until everyone has a chance to upgrade their mail software 
to use the new record ;-p