lua-resty-waf is a web application firewall implemented in Lua for OpenResty/NGINX, designed to run inline at the edge with low overhead. It inspects requests and responses during NGINX phases, applying rule logic and anomaly scoring to detect patterns like SQL injection, cross-site scripting, and protocol abuse. Rules are organized into policies with configurable actions—block, log, or allow—and can leverage shared dictionaries for counters, rate limits, and caching decisions. Because it runs...