On Thu, 19 Feb 1998, Perry E. Metzger wrote:
John R Levine writes:
Are there any routers currently available that can do port 25 spoofing for dialup users? That is, when the user attempts to connect to port 25 anywhere, he in fact connects to port 25 on your own SMTP server instead.
In case it's not obvious, it's for spam management.
It seems simple enough to block all outgoing SMTP to anything but your own server, and to apply such a filter on your dialups. I don't know if the more complex solution you propose is worth it -- the users will
Couldn't this be done with transparent proxy just as some ISP's do it for web proxying/caching? CONFIG_IP_TRANSPARENT_PROXY This enables your Linux firewall to transparently redirect any network traffic originating from the local network and destined for a remote host to a local server, called a "transparent proxy server". This makes the local computers think they are talking to the remote end, while in fact they are connected to the local proxy. Redirection is activated by defining special input firewall rules (using the ipfwadm utility) and/or by doing an appropriate bind() system call. ------------------------------------------------------------------ Jon Lewis <jlewis@fdt.net> | Unsolicited commercial e-mail will Network Administrator | be proof-read for $199/message. Florida Digital Turnpike | ______http://inorganic5.fdt.net/~jlewis/pgp for PGP public key____