I need to check letter's heading (subject) and if subject doesn't contain some passphrase check this letter with greylisting or rbl. I can't understand how can I solve such problem with postfix. My server should check all smtpd_*_restrictions for SMTP headers, then start to receive data and if data doesn't contain some passphrase, check smtpd_data_restrictions, in which I want to add greylisting. So I need some option like check_policy_service for smtpd_data_restrictions, which will send to external service not only SMTP headers, but also a letter's body. And then add to main.cf something like
smtpd_data_restrictions = reject_unauth_pipelining *check_data??? # What I should place here? * check_policy_service inet:localhost:60000 # Greylisting reject_rbl_client bl.spamcop.net # RBL My company has a lot of new clients and my managers should be able to say some passphrase to client (by phone eg) for passing my spamfilter without checking RBL and without Greylisting. I can't add clients to whitelist, so passphrase is the easest solution for my users, but I can't understand how to implement it with Postfix. In a few words: I need to check data *before*accepting a letter to be able to reject a letter with SMTP error code based on its content. How can I do it with postfix?
