Dave Lugo wrote:
> On Sun, 15 Oct 2006, Marc Perkel wrote:
>
>> Looking for ACL rules that I can use to drop bad sender domains. This
>> would include domains that don't exist. Domains where DNS servers refuce
>> the request as opposed to just failing to respond, and other things that
>> let me know the domain itself is bogus.
>>
>>
>
> Didn't this get covered a few weeks ago?
>
> defer !verify = sender
>
> Trying to get much more fancy than that may result
> in 5xx'ing mail from domains that are having temporary
> issues. (at least that's my understanding)
>
>
I don't want to defer it. I have some targeted sender verification but
raw sender verify has too many false positives. What I want to do is do
a hard bounce on domains that don't exist. Here's some code I found but
it doesn't catch everything.
drop message = No MX or A record for sender domain F=$sender_address
!senders = :
condition = ${if and {\
{eq {${lookup
dnsdb{a=$sender_address_domain}{$value}{NONE}}}{NONE}}\
{eq {${lookup
dnsdb{mx=$sender_address_domain}{$value}{NONE}}}{NONE}}\
}\
{yes}{no}}
This could probably use some cleanup.