location = {{ ANTIBOT_URI }} { default_type 'text/html'; if ($request_method = GET) { content_by_lua_block { local cookie = require "cookie" local recaptcha = require "recaptcha" local logger = require "logger" if not cookie.is_set("uri") then logger.log(ngx.WARN, "ANTIBOT", "recaptcha fail (1) for " .. ngx.var.remote_addr) return ngx.exit(ngx.HTTP_FORBIDDEN) end local code = recaptcha.get_code("{{ ANTIBOT_URI }}", "{{ ANTIBOT_RECAPTCHA_SITEKEY }}") ngx.say(code) } } if ($request_method = POST) { access_by_lua_block { local cookie = require "cookie" local recaptcha = require "recaptcha" local logger = require "logger" if not cookie.is_set("uri") then logger.log(ngx.WARN, "ANTIBOT", "recaptcha fail (2) for " .. ngx.var.remote_addr) return ngx.exit(ngx.HTTP_FORBIDDEN) end ngx.req.read_body() local args, err = ngx.req.get_post_args(1) if err == "truncated" or not args or not args["token"] then logger.log(ngx.WARN, "ANTIBOT", "recaptcha fail (3) for " .. ngx.var.remote_addr) return ngx.exit(ngx.HTTP_FORBIDDEN) end local token = args["token"] local check = recaptcha.check(token, "{{ ANTIBOT_RECAPTCHA_SECRET }}") if check < {{ ANTIBOT_RECAPTCHA_SCORE }} then logger.log(ngx.WARN, "ANTIBOT", "recaptcha fail (4) for " .. ngx.var.remote_addr .. " (score = " .. tostring(check) .. ")") return ngx.exit(ngx.HTTP_FORBIDDEN) end cookie.set({recaptcha = "ok"}) return ngx.redirect(cookie.get("uri")) } } }