Nov 05 2010

Checking IPs

Category: WordPressChrisM @ 10:44 pm

This is the first of two plug-ins by the same author, who goes by the moniker StarGazer. This first one is WP-Blackcheck, and the idea is quite simple. Rather than simply relying on your anti-spam plug-in (if you haven’t installed anything extra, this will most likely be Akismet) to notice when there are unwanted commercial links placed in a comment, WP-Blackcheck consults with a central server which holds a blacklist of known spammers, or rather the IP addresses they tend to use.
If someone attempts to leave a comment when they are using an IP address in the blacklist, they are presented with a message explaining why the comment won’t be processed, and if they feel they are on the list and shouldn’t be, they can send a message. This is useful because due to DHCP leases on IP addresses, it is possible that the spammer only used the IP address for a few days. If someone then leaves a genuine comment on a relevant post, they can let the author know they are not spamming.
The blacklist itself is updated by anyone who uses the plug-in, as when any spam that gets past WP-BlackCheck is discovered by Akismet, the details are recorded. Once you click the report spam link at the top of your dashboard, the IP addresses are noted, and if the trigger level is reacher (in terms of number of spam comments from one IP address), then the address is added to the central blacklist, to ensure the spammer can’t even try and sneak any comments past Akismet (or your preferred spam checking plug-in) in the future.