feat: added functionality to set quasi-random cookie if captcha is passed

haproxy/Dockerfile

@@ -113,7 +113,8 @@ RUN wget "https://luarocks.org/releases/luarocks-3.3.1.tar.gz" &&\
 
 RUN /usr/local/bin/luarocks install luasocket &&\
     /usr/local/bin/luarocks install luasec &&\
-    /usr/local/bin/luarocks install net-url
+    /usr/local/bin/luarocks install net-url &&\
+    /usr/local/bin/luarocks install md5
 
 ENTRYPOINT ["/usr/local/bin/docker-entrypoint.sh"]
 

scripts/hcaptcha.lua

@@ -3,6 +3,9 @@ hcaptcha = {}
 local url = require("net.url")
 local https = require("ssl.https")
 local json = require("json")
+local utils = require("utils")
+
+local floating_hash = utils.get_floating_hash()
 
 function hcaptcha.view(applet)
     local hcaptcha_secret = os.getenv("HCAPTCHA_SECRET")
@@ -34,7 +37,7 @@ function hcaptcha.view(applet)
 
             if api_response.success == true then
                 print("HCAPTCHA SUCCESSFULLY PASSED")
-                print("... success captcha flow goes here ...")
+                applet:add_header("set-cookie", string.format("z_ddos_protection=%s; Max-Age=14400", floating_hash))
             else
                 print("HCAPTCHA FAILED", body)
             end

scripts/utils.lua

@@ -0,0 +1,18 @@
+local _M = {}
+local md5 = require("md5")
+
+function _M.get_hostname()
+    local f = io.popen ("/bin/hostname")
+    local hostname = f:read("*a") or ""
+    f:close()
+    hostname =string.gsub(hostname, "\n$", "")
+    return hostname
+end
+
+function _M.get_floating_hash()
+    -- This ensures that a cookie is rotated every day
+    return md5.sumhexa(_M.get_hostname() .. os.date("%d"))
+end
+
+return _M
+