On Fri, Apr 13, 2007 at 10:17:51PM -0400, Paolo Supino wrote: > Hi Bob > > The webapp does talk to a real mail server: on localhost (IIS6 SMTP > service). When a spammers abuses the webapp the email is actually sent > via the local mail server and not directly from the webapp to all the > mail servers on the Internet. Rate limiting isn't an option because > emails must be out the door within a very short time frame from the > moment a set of events is triggered in the webapp. > Right now the only way I can think of is limit the SMTP service to > connect only to authorized remote SMTP servers that I will manage > manually (I'm in the process of checking how often I would have to > change the list to see if it's feasible). You wrote that I can do it > with spamd, how? > Another option I thought of is setting up a sendmail relay on another > computer and let that sendmail only relay specific emails according to a > set of criteria (that fit only valid emails).
You are going about this all wrong. First step is finding a suitable blunt instrument and getting the developers to fix it. The second step is configuring rate limiting, along the lines of '1000 mails/hour'; this will allow a large batch of e-mail to get through immediately, but stop spammers. What you're planning now is both less effective and way more work. Joachim