--- [ Seth Mattinen <[email protected]> wrote ] ----------------------------------- On 9/15/14, 11:06, Animal Farm wrote:
Paul, you might want to send that log file output from my mail server to someone at Amazon about the missing SMTP QUIT commands. That breaks the RFC and my mail server obviously doesn't like that, which I can't change because the connection rate-limiting is very helpful in stopping or slowing down attacks. I don't know what would cause SMTP commands to be dropped on their end. Anyway.. I don't touch our cPanel server unless it's absolutely necessary. Usually cPanel themselves break stuff and I make them log in and fix it.
There's no legitimate reason to not send QUIT. Looking at my logs I see possibly the same problem:
2014-09-15T11:06:36-07:00 mail postfix/smtpd[30716]: timeout after END-OF-MESSAGE from a9-91.smtp-out.amazonses.com[54.240.9.91]
Postfix doesn't say it's not because of lack of QUIT, but I'd bet if I turn on session debugging for an SES connection it will be.
The proper sequence for the DATA phase should be "DATA" followed by the data, then a lone "." indicating end-of-data (EOD), a response code, then a "QUIT". Maybe SES is assuming EOD response will always be a 2xx code? That would be bad because RFC allows for non-2xx codes in response to EOD.
~Seth
