I have an issue where some of our web servers are passing bad email addresses to a Postfix server, which is then doing some sort of re-write on the address to make it compliant, then passing it to our outbound server (PowerMTA). PowerMTA is then attempting to send the message, which fails as the recipient address doesn't exist. I have a process that reads the PowerMTA log files and produces an XML report for another application to read and remove bad addresses from our database. This final process is unable to deal with these addresses, as it does not consider the form of the address to be "correct" and throws an error. I have no control over this final process. I thought for the longest time either PowerMTA or my log processing / report generation tool was at fault, due to the near-impossibility of a Unix shell script to properly process a CSV file. I finally determined the problem is at Postfix (or at least, could be solved at the Postfix level.)
A sample email address that is being sent to Postfix would be: [ paku_paku..love-gateau....@docomo.ne.jp ]. Postfix is turning this into [ "paku_paku..love-gateau..z7"@docomo.ne.jp ] (braces and whitespace add by me. Everything inside the braces is literal.) It took me a while to track this down to Postfix as the Postfix mail log contained the original address as passed by the web server (without the double quotes) and everything in the PowerMTA logs contained the double quotes. I assumed PowerMTA was simply logging it that way due to the CSV file format. I finally proved it was Postfix adding it by doing a Wireshark sniff on my own workstation, first connecting directly to my PowerMTA server and seeing the SMTP stream showing the original form, and this form appearing in the PowerMTA log, then connecting to my local Postfix instance and seeing the Postfix to PowerMTA SMTP stream showing the later version. While it may be "correct" for Postfix to munge that bogus email address into an RFC compliant string, is there a way to tell it not to do that, or even just discard the message without attempting to relay it? At this point this is more to satisfy my personal curiosity how to do this than anything, as I'm in the process of re-architecting our mail flow in a way that eliminates Postfix entirely (for reasons that have nothing to do with this particular problem.) -- Andrew Edelstein, RHCE Certificate number 120-074-182 and...@pure-chaos.com https://andrew.pure-chaos.com/
