lua-resty-ipcidr

A simple and very fast function to check against CIDR

Overview

access_by_lua_block {
    local ipcidr = require("resty.ipcidr")
    local whitelist_ips = {
      "127.0.0.1",
      "10.10.10.0/24",
      "192.168.0.0/16",
  }
    if not ipcidr.ip_in_cidrs(ngx.var.remote_addr, whitelist_ips) then
      return ngx.exit(ngx.HTTP_FORBIDDEN)
    end
}

Methods

ip_in_cidrs

syntax: bool, err = ipcidr.ip_in_cidrs(ip, cidrs)

Takes a string IPv4 address and a table of parsed CIDRs.

Returns a true or false if the IP exists within any of the specified networks.

Returns nil and an error message with an invalid IP