From d7e3c9d1e968a1229f5a1fabb547605a42d59d3c Mon Sep 17 00:00:00 2001
From: Rsclub2_2 <philipp@wagnersnetz.de>
Date: Mon, 24 Jun 2024 21:38:02 +0200
Subject: [PATCH] =?UTF-8?q?udp=5Frelay.py=20hinzugef=C3=BCgt?=
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---
 udp_relay.py | 86 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 86 insertions(+)
 create mode 100644 udp_relay.py

diff --git a/udp_relay.py b/udp_relay.py
new file mode 100644
index 0000000..17a7dfd
--- /dev/null
+++ b/udp_relay.py
@@ -0,0 +1,86 @@
+import socket
+import threading
+import time
+import argparse
+import hashlib
+
+# Konfigurationsparameter
+LOOPBACK_TIMEOUT = 1  # Zeit in Sekunden, um Loopback zu verhindern
+
+# Speichert gesendete Nachrichten-Hashes für eine kurze Zeit, um Loopback zu verhindern
+recent_messages = {}
+
+def create_socket(port, bind_ip=''):
+    """Erstellt und konfiguriert den UDP-Socket zum Lauschen auf Broadcast-Nachrichten."""
+    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+    sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
+    sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
+    sock.bind((bind_ip, port))
+    return sock
+
+def hash_message(message):
+    """Erzeugt einen Hash-Wert für eine Nachricht."""
+    return hashlib.sha256(message).hexdigest()
+
+def should_forward_message(message):
+    """Überprüft, ob eine Nachricht innerhalb des Zeitlimits bereits gesendet wurde."""
+    current_time = time.time()
+    message_hash = hash_message(message)
+    
+    # Entferne alte Nachrichten
+    for msg_hash in list(recent_messages):
+        if current_time - recent_messages[msg_hash] > LOOPBACK_TIMEOUT:
+            del recent_messages[msg_hash]
+    
+    if message_hash in recent_messages:
+        print(f"Message already forwarded recently: {message}")
+        return False
+    
+    recent_messages[message_hash] = current_time
+    return True
+
+def relay_messages(listen_ip, listen_port, relay_ip, relay_port):
+    sock = create_socket(listen_port, listen_ip)
+    print(f"Listening for UDP broadcasts on {listen_ip}:{listen_port}...")
+
+    while True:
+        data, addr = sock.recvfrom(1024)  # Puffergröße 1024 Bytes
+        print(f"Received message on {listen_ip}:{listen_port} from {addr}: {data}")
+
+        # Prüfen, ob die Nachricht mit "RCVDPKT: \"TELNET\" \"\" \"DX de", "GAB:" oder "SpotUdp" beginnt
+        if (data.startswith(b'RCVDPKT: "TELNET" "" "DX de') or data.startswith(b'GAB:') or data.startswith(b'SpotUdp')):
+            if should_forward_message(data):
+                print(f"Forwarding message to {relay_ip}:{relay_port}")
+                relay_socket = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+                relay_socket.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
+                relay_socket.sendto(data, (relay_ip, relay_port))
+                relay_socket.close()
+            else:
+                print(f"Skipped forwarding message due to recent forwarding: {data}")
+
+def main():
+    parser = argparse.ArgumentParser(description="Bidirektionales UDP-Relay mit zeitbasierter Loopback-Prüfung")
+    parser.add_argument('--ip1', type=str, required=True, help='Erste IP-Adresse')
+    parser.add_argument('--port1', type=int, required=True, help='Erster Port')
+    parser.add_argument('--ip2', type=str, required=True, help='Zweite IP-Adresse')
+    parser.add_argument('--port2', type=int, required=True, help='Zweiter Port')
+    
+    args = parser.parse_args()
+
+    ip1 = args.ip1
+    port1 = args.port1
+    ip2 = args.ip2
+    port2 = args.port2
+
+    # Starten von zwei Threads für bidirektionales Relay mit zeitbasierter Loopback-Prüfung
+    thread1 = threading.Thread(target=relay_messages, args=(ip1, port1, ip2, port2))
+    thread2 = threading.Thread(target=relay_messages, args=(ip2, port2, ip1, port1))
+
+    thread1.start()
+    thread2.start()
+
+    thread1.join()
+    thread2.join()
+
+if __name__ == "__main__":
+    main()