Add simple port scanner script

README.md

@@ -1 +1,17 @@
-# Chapy
+# Chapy
+
+This repository contains a simple Python script to scan ports on a given host. It can also attempt to connect to one of the detected open ports.
+
+## Usage
+
+```
+python3 port_scanner.py <host> [--start START_PORT] [--end END_PORT] [--connect PORT]
+```
+
+Example:
+
+```
+python3 port_scanner.py 127.0.0.1 --start 1 --end 1024 --connect 22
+```
+
+This will scan ports `1` through `1024` on `127.0.0.1` and attempt to connect to port `22` if it is open.

port_scanner.py

@@ -0,0 +1,48 @@
+import argparse
+import socket
+from typing import List
+
+
+def scan_ports(host: str, start_port: int, end_port: int) -> List[int]:
+    """Scan a range of ports on the given host and return a list of open ports."""
+    open_ports = []
+    for port in range(start_port, end_port + 1):
+        with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
+            sock.settimeout(0.5)
+            result = sock.connect_ex((host, port))
+            if result == 0:
+                open_ports.append(port)
+    return open_ports
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(description="Simple port scanner")
+    parser.add_argument("host", help="Host to scan, e.g., 127.0.0.1")
+    parser.add_argument("--start", type=int, default=1, help="Start port (default: 1)")
+    parser.add_argument("--end", type=int, default=1024, help="End port (default: 1024)")
+    parser.add_argument("--connect", type=int, help="Port to connect to after scanning")
+    args = parser.parse_args()
+
+    print(f"Scanning ports {args.start}-{args.end} on {args.host}...")
+    open_ports = scan_ports(args.host, args.start, args.end)
+    if open_ports:
+        print("Open ports found:", ", ".join(map(str, open_ports)))
+    else:
+        print("No open ports found in the specified range.")
+
+    if args.connect:
+        if args.connect in open_ports:
+            print(f"Attempting to connect to {args.host}:{args.connect}...")
+            with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
+                try:
+                    sock.settimeout(2)
+                    sock.connect((args.host, args.connect))
+                    print(f"Successfully connected to {args.host}:{args.connect}")
+                except OSError as exc:
+                    print(f"Connection failed: {exc}")
+        else:
+            print(f"Port {args.connect} is not open or not in the scanned range.")
+
+
+if __name__ == "__main__":
+    main()