[ietf-dkim] DKIM signature can mean it's safe to generate bounce?

[Douglas Otis]

On Jul 6, 2007, at 5:19 PM, Steve Atkins wrote:

>
> On Jul 6, 2007, at 5:09 PM, Dave Crocker wrote:
>
>> Folks,
>>
>> I'm not sure whether this fits into SSP or not, since it does not  
>> seem to require that a record be published. However...
>>
>> It seems to me that if a message has a DKIM signature and the  
>> signing domain matches the domain in the rfc2821.MailFrom command,  
>> then it is safe to generate a bounce message to that address.
>>
>> By 'safe' I mean that one can be confident that the mail will not  
>> go to an unwitting victim of a spoofed address.
>>
>> Am I missing something?
>
> If the mail is sent by dick at earthlink.net (or a virus on their  
> machine), with an envelope from address of jane at earthlink.net out  
> through the DKIM stamping earthlink smarthost and you generate a  
> bounce, that bounce will go to Jane.

Earthlink added the signature.  This falls into the same category as  
would any replay problem.  Once again, tpa-ssp helps cope with that  
issue as well.

-Doug