1. Building an SYN Scanner:
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from scapy.all import IP, TCP, sr1

def syn_scan(target, port):
    pkt = IP(dst=target) / TCP(dport=port, flags="S")
    response = sr1(pkt, timeout=1, verbose=0)
    if response and response.haslayer(TCP):
        if response.getlayer(TCP).flags == 0x12:  # SYN-ACK
            print(f"Port {port} is open on {target}")
        elif response.getlayer(TCP).flags == 0x14:  # RST-ACK
            print(f"Port {port} is closed on {target}")
    else:
        print(f"Port {port} is filtered on {target}")

target_ip = "192.168.1.1"
for port in range(20, 100):
    syn_scan(target_ip, port)


2. Running the SYN Scanner:
---------------------------

* Run the script against a controlled system.
* Use Wireshark to visualize the traffic.


3. Modifications & Enhancements:
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* Add multiple targets.

* Multi-threading for faster scanning.

* Scan only common ports.