Plugin for YOURLS 1.5+: Antispam

What for

This is an antispam plugin that uses major DNS blacklists to detect spam, at link creation time and at visit time :

• URL are checked against the blacklist when short urls are created.
• They are also randomly checked when someone follows a short URL and if the link has been compromised recently, the short URL is deleted. To only block the redirect and keep the link for an admin to review, return false from the ozh_yourls_antispam_delete_on_redirect filter.

DNS backlists used: zen.spamhaus.org, multi.surbl.org, bl.spamcop.net. Use the ozh_yourls_antispam_list filter to change them. Only an A record in 127.0.0.0/8 counts as listed (not the "query refused" answers 127.0.0.1 and 127.255.255.x), and a list that also lists the name invalid (RFC 5782) is treated as broken and skipped, so a dead or wildcarding list can't flag every link.

How to

• In /user/plugins, create a new folder named antispam
• Drop these files in that directory
• Go to the Plugins administration page and activate the plugin
• Have fun

Disclaimer - please read

Checking against DNS blacklists may or may not work for you, this may depend on the type of spam you are getting and on other factors such as your server IP, your server ISP, the DNS you are using. It may even result in all domains being blacklisted from your server. Try and see.

If you're not sure what DNS blacklists are, you can check out the DNSBLs list.

If you're still not sure this plugin is for you, we recommend you use another plugin, such as Google Safe Browsing, or a plugin that will add a captcha to your public interface -- see the plugin list at https://github.com/YOURLS/awesome-yourls.