From 1223f1f94a110eb0ec50b9f35cf03c5757cc0603 Mon Sep 17 00:00:00 2001
From: Sven Heidemann <sven.heidemann@sh-edraft.de>
Date: Wed, 5 Nov 2025 22:00:42 +0100
Subject: [PATCH] =?UTF-8?q?ocsense.lua=20hinzugef=C3=BCgt?=
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---
 ocsense.lua | 60 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)
 create mode 100644 ocsense.lua

diff --git a/ocsense.lua b/ocsense.lua
new file mode 100644
index 0000000..f18ab34
--- /dev/null
+++ b/ocsense.lua
@@ -0,0 +1,60 @@
+local event = require("event")
+local minitel = require("minitel")
+local serialization = require("serialization")
+
+local PORT = 5353
+local LOCAL_DOMAIN = "home1" -- oder "home1.net"
+local records = {}
+local running = true
+
+print("[ocsense] DNS/UUID-Server gestartet auf port " .. PORT)
+print("[ocsense] Strg+C zum Beenden")
+
+local function stripLocalDomain(name)
+  if name:sub(-#LOCAL_DOMAIN) == LOCAL_DOMAIN then
+    local dot = name:sub(-( #LOCAL_DOMAIN + 1 ), -( #LOCAL_DOMAIN + 1 ))
+    if dot == "." then
+      return name:sub(1, -( #LOCAL_DOMAIN + 2 ))
+    else
+      return name:sub(1, -( #LOCAL_DOMAIN + 1 ))
+    end
+  end
+  return name
+end
+
+while running do
+  local ev, fromName, port, data, fromAddr = event.pull()
+  if ev == "interrupted" then
+    print("[ocsense] beendet durch Strg+C")
+    running = false
+
+  elseif ev == "net_msg" and port == PORT and type(data) == "string" then
+    local cmd, a, b = data:match("^(%S+)%s*(%S*)%s*(%S*)")
+
+    if cmd == "REG" and a ~= "" and b ~= "" then
+      -- a = hostname, b = hardware UUID
+      records[a] = b
+      print("[ocsense] REG", a, "=>", b)
+
+    elseif cmd == "Q" and a ~= "" then
+      local replyto = (b ~= "" and b) or fromName
+      local addr = records[a]
+
+      -- lokale Domain abstreifen, falls nötig
+      if not addr then
+        local short = stripLocalDomain(a)
+        if short ~= a then
+          addr = records[short]
+        end
+      end
+
+      if addr then
+        minitel.usend(replyto, PORT, "A " .. a .. " " .. addr)
+        print("[ocsense] A", a, "->", addr)
+      else
+        minitel.usend(replyto, PORT, "NX " .. a)
+        print("[ocsense] NX", a)
+      end
+    end
+  end
+end