from scapy.all import IP, TCP, sr1 import sys from datetime import datetime

Define common services for open ports (for better reporting)

SERVICE_NAMES = { 21: "FTP", 22: "SSH", 23: "TELNET", 25: "SMTP", 53: "DNS", 80: "HTTP", 110: "POP3", 143: "IMAP", 443: "HTTPS", 3389: "RDP" }

def syn_scan_ports(target, start_port, end_port): """ Performs a SYN/Stealth scan using Scapy on a range of ports. """ print(f"--- Starting SYN Scan on {target} at {datetime.now()} ---")

# We rely on Scapy to resolve the target IP
target_ip = target
open_ports = []

# Iterate through the port range
for port in range(start_port, end_port + 1):
    # 1. Craft the packet: IP layer + TCP layer (with the SYN flag set)
    ip_layer = IP(dst=target_ip)
    tcp_layer = TCP(dport=port, flags="S") 
    
    # 2. Combine and send the packet
    # sr1 sends the packet and waits for only the first response.
    # timeout is shorter as SYN scans are quick.
    # verbose=False suppresses Scapy's default output.
    response = sr1(ip_layer / tcp_layer, timeout=0.1, verbose=False)
    
    if response:
        # 3. Analyze the response:
        # A reset flag (R) means the port is closed.
        # An ACK-SYN flag (SA or 0x12) means the port is open.
        
        # Check for the TCP layer and the 'SA' flag (0x12)
        if response.haslayer(TCP) and response.getlayer(TCP).flags == 0x12:
            service = SERVICE_NAMES.get(port, "Unknown")
            print(f"[+] Port {port} ({service}): Open")
            open_ports.append(port)
    
print("--- Scan Complete ---")
if open_ports:
    print(f"Open ports found: {open_ports}")
else:
    print("No open ports found in the specified range.")

if name == "main": if len(sys.argv) != 4: print("Usage: python scapy_scanner.py <start_port> <end_port>") print("Example: python scapy_scanner.py 127.0.0.1 1 1024") sys.exit()

target = sys.argv[1]
start_port = int(sys.argv[2])
end_port = int(sys.argv[3])

try:
    syn_scan_ports(target, start_port, end_port)
except Exception as e:
    print(f"[!] An error occurred. Ensure you have root/admin privileges for Scapy operations. Error: {e}")