initial concept of the script

PortGenScript.py

@@ -0,0 +1,87 @@
+"""
+Random port generator that skips common / less‑secure ports.
+"""
+
+import random
+import socket
+
+# ------------------------------------------------------------
+# 1. Build a set of excluded ports
+# ------------------------------------------------------------
+
+EXCLUDED_PORTS = {
+    # 0–1023 (well‑known)
+    *range(0, 1024),
+
+    # Common web / admin
+    80, 443, 8080, 8000, 5000, 5001,
+
+    # Common database / cache
+    3306, 5432, 6379, 27017, 11211, 11212,
+
+    # Common mail / DNS / SNMP
+    25, 110, 143, 53, 162, 389, 636, 995, 993,
+
+    # Remote‑shell & file transfer
+    22, 23, 21, 3389, 5900, 5901, 5902,
+
+    # SMB / NetBIOS
+    139, 445,
+
+    # Dynamic “ephemeral” ports that are often abused
+    *range(49152, 49163),  # 49152‑49162
+    5000, 5001, 5002, 5003, 5004, 5005,
+    6000, 6001, 6002, 6003,
+}
+
+# ------------------------------------------------------------
+# 2. Helper to check whether a port is free on the local machine
+# ------------------------------------------------------------
+def is_port_in_use(port: int, host: str = "0.0.0.0") -> bool:
+    """Return True if any socket is listening on `port`."""
+    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
+        s.settimeout(0.1)
+        try:
+            s.bind((host, port))
+            return False
+        except (OSError, socket.error):
+            return True
+
+# ------------------------------------------------------------
+# 3. Random‑port generator
+# ------------------------------------------------------------
+def random_secure_port(
+    *,
+    min_port: int = 1024,
+    max_port: int = 65535,
+    max_tries: int = 1000,
+    check_in_use: bool = True,
+) -> int:
+    """
+    Return a random port number that is:
+    * >= min_port and <= max_port
+    * not in EXCLUDED_PORTS
+    * optionally not currently in use (if check_in_use=True)
+
+    Raises RuntimeError if it cannot find a suitable port after `max_tries`.
+    """
+    rng = random.SystemRandom()   # cryptographically stronger RNG
+
+    for _ in range(max_tries):
+        candidate = rng.randint(min_port, max_port)
+        if candidate in EXCLUDED_PORTS:
+            continue
+        if check_in_use and is_port_in_use(candidate):
+            continue
+        return candidate
+
+    raise RuntimeError(
+        f"Could not find an unused port after {max_tries} attempts."
+    )
+
+# ------------------------------------------------------------
+# 4. Example usage
+# ------------------------------------------------------------
+if __name__ == "__main__":
+    port = random_secure_port()
+    print(f"Generated secure random port: {port}")