Will McDonald wrote:
On 12/03/06, Sam Drinkard sam@wa4phy.net wrote:
A while back, I posted a note asking if anyone had any ideas why the /etc/mail/access file was not being parsed or utilized in the efforts to stop spam and junk mail. I just looked over things again, and have still not found any reason why it still permits the TLD's I have listed to pass thru. I also thought perhaps there might be some "upper limit" to the number of entries sendmail could handle. What do the sendmail guru's think about that idea? I may reduce the number of entries from the current 275 +/- down to just the most offensive TLD's and see what happens. Short of that, are there any other thoughts ya'll might have as to why it still passes the stuff I want blocked?
I don't know the ins-and-outs of Sendmail access well but does it base its decision purely on the "From" address, which as we all know isn't necessarily where a message originates. Or could it be basing the access decision on the initial Received: from address, and/or that addresses reverse lookup, in the header?
In which case, a spam could originate from mail.blah.com and access would accept it but the message itself would appear to come from spammers@domain.ru. You'd accept the message inspite of having .ru denied in your access.
Just a thought.
Will. _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos
As far as I know Will, sendmail looks at the access database, and will not allow a connection from the sending host if that particular IP or hostname happens to be in there. The access list *used* to work, but as I mentioned, I'm wondering if perhaps I've hit an upper limit or exceeded a limit where nothing in there is being parsed now. I don't go by hostname when blocking. I look at the sending host IP and block that. Headers from sendmail tell who or what connected to the port or tried to connect.
Sam