Is it possible to sign smtp from with DKIM? I clarify that I am not talking
about the header from.
I have installed opendkim and can only sign the header from.
What I am seeing is that some emails that I receive in the different Gmail
tabs, for example Promotions, have a double dkim key:
Authentication-Results: mx.google.com;
dkim=pass header.i=@stackoverflow.email header.s=s1
header.b=S0yxBc6Y;
dkim=pass header.i=@sendgrid.info header.s=smtpapi header.b=uYee9Qd0;
The from address is stackoverflow.email but exits and second dkim from
sendgrid.info.
My idea is to sign the email twice, but I don't understand how to do it.
Does anyone use double signed?
Regards,
