You can either configure it though the terminal, in the Sharing pane of System Preferences (though, it's a very basic interface), or through a third-party tool.
BrickHouse is a free front-end to that built-in firewall. It can do exactly what you are requesting, blocknig individual IPs. I use it and recommend it to everyone I know that's looking for a good firewall.
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You can either configure it though the terminal, in the Sharing pane of System Preferences (though, it's a very basic interface), or through a third-party tool.
BrickHouse is a free front-end to that built-in firewall. It can do exactly what you are requesting, blocknig individual IPs. I use it and recommend it to everyone I know that's looking for a good firewall.