[opendmarc-dev] handle empty envelope sender

[Andreas Schulze]

Hi,

I run an autoresponder <echo at signing-milter.org>. Mails sent back to the Sender
are dkim signed and normaly pass also a dmarc check. Of course the envelope sender is empty.

opendmarc logs:
Feb  5 09:31:35 dmarc opendmarc[24455]: 3Z0fCB34Jxz259H: can't parse validated SPF address <<>>
Feb  5 09:31:35 dmarc opendmarc[24455]: 3Z0fCB34Jxz259H: pass

I think it's a postfix specific detail how the milter api is implemented:
postfix may call a milter for smtp and nonsmtp message transfers.

xxfi_envfrom for example provides the sender address.
This value is surrounded by postfix with <> if called in smtp context but has no <> in nonsmtp mode.

Summary:
argv[0] in xxfi_envfrom looks in postfix:

SMTP-Mode:
nonempty sender: '<user at example.org>'
empty sender: '<>'

NON-SMTP-Mode:
nonepty sender: 'user at example.org'
empty sender: ''

To be precise:
This is not a bugreport. I only like to remind the (postfix specific?) behavior.

Andreas