About spamdyke
spamdyke is a filter for monitoring and intercepting SMTP connections between a remote host and a qmail server. Spam is blocked while the remote server (spammer) is still connected; no additional processing or storage is needed.
In addition to all of its anti-spam filters, spamdyke also includes a number of features to enhance qmail.
Best of all, using spamdyke does not require patching or recompiling qmail!
Anti-Spam Filters
spamdyke boasts a large number of filters for blocking mail from remote servers. Every filter is individually configurable.
spamdyke's reverse DNS filters can:
- Require reverse DNS names.
- Require reverse DNS names to resolve with IP addresses.
- Require reverse DNS names to be real, not dynamically assigned.
- Require the sender's domain name to have a valid mail exchanger (MX).
spamdyke's blacklist and whitelist filters can:
- Search local IP and reverse DNS blacklist/whitelist files.
- Search DNS realtime blacklists/whitelists (DNS RBLs).
- Search DNS righthand-side blacklists/whitelists (DNS RHSBLs).
- Search sender and recipient blacklist/whitelist files.
- Search message headers for specific content.
spamdyke's graylist(/greylist) filters can:
- Graylist specific recipient domains (activated per domain).
- Graylist connections from specific IP addresses or reverse DNS domains.
- Enforce minimum and maximum ages for graylist entries.
- Skip graylisting for specific domains, IP addresses or reverse DNS domains.
spamdyke's other filters can:
- Stop earlytalkers (remote servers that send data before the SMTP greeting banner is sent).
- Limit the maximum number of recipients per message.
- Enforce idle timeouts and absolute timeouts.
- Prevent unauthorized relaying.
- Stop spam that appears to come from the recipient's address.
See the README file for full details.
Additional Features
spamdyke has additional features you will love:
- Readable logging, using syslog, so you can actually monitor your qmail server and save your log files.
- Full SMTP AUTH support, so your users can bypass all filters, even from remote locations. spamdyke can provide SMTP AUTH even if qmail is completely unpatched.
- Full TLS support, so your users can send mail securely. spamdyke can provide TLS even if qmail is completely unpatched.
- Log all SMTP traffic to files so you can diagnose connection problems.
- Support available through an active mailing list.
See the README file for full details.