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Dongho Kim
2024-11-01 00:07:17 +09:00
parent 65986c1ca5
commit 2858c522ef
5 changed files with 197 additions and 138 deletions
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52
Task pwn02/week02/easy/client.py
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@ -15,55 +15,73 @@ log = logging.getLogger(__name__)
TCP_CLIENTS = {} # ((IP, port) -> [sent_packets])
# SERVER_IP = '131.159.15.68' # don't use the domain name in this case
SERVER_IP = "127.0.0.1" # don't use the domain name in this case
SERVER_IP = '127.0.0.1' # don't use the domain name in this case
SERVER_PORT = 20102
COOKIE_SECRET = "TASTY_COOKIES123"
COOKIE_SECRET = 'TASTY_COOKIES123'
SRC_PORT = randrange(10000, 50000)
def generate_syn_cookie(client_ip: str, client_port: int, server_secret: str):
# TODO: please implement me!
return 0
hash_input = f'{client_ip}{client_port}{server_secret}'.encode()
return int(hashlib.sha256(hash_input).hexdigest(), 16) % (2**32)
def handle_packet(packet: Packet):
# TODO: please implement me!
packet.show()
if packet.haslayer(TCP) and packet[TCP].dport == SRC_PORT and "S" == packet[TCP].flags:
server_seq = packet[TCP].seq
ip = IP(dst=SERVER_IP)
ack = TCP(sport=SRC_PORT, dport=SERVER_PORT, flags='A', seq=packet[TCP].ack, ack=1337)
send(ip / ack)
print("Sent ACK packet with modified ACK number:", server_seq)
# Function to send the initial SYN packet
def send_initial_syn():
# Generate the SYN cookie
cookie = generate_syn_cookie(SERVER_IP, SERVER_PORT, COOKIE_SECRET)
# Construct the IP and TCP layers
ip = IP(dst=SERVER_IP)
syn = TCP(sport=SRC_PORT, dport=SERVER_PORT, flags='S', seq=cookie)
# Send the packet
send(ip / syn)
print("Sent initial SYN packet with cookie:", cookie)
# Function to start the packet sniffing
def start_sniffing():
def start_sniffing():
sniff(
filter=f"tcp port {SERVER_PORT}", # this should filter all packets relevant for this challenge.
filter=f'tcp port {SERVER_PORT}', # this should filter all packets relevant for this challenge.
prn=handle_packet,
store=False,
monitor=True,
iface="eth0", # set to your interface. IMPORTANT: SET TO enX0 FOR AUTOGRADER!!!
iface='lo', # set to your interface. IMPORTANT: SET TO enX0 FOR AUTOGRADER!!!
)
COOKIE = generate_syn_cookie(SERVER_IP, SERVER_PORT, COOKIE_SECRET)
# Run the server in a separate thread
def main():
conf.use_pcap = False
server_thread = threading.Thread(target=start_sniffing)
server_thread.start()
time.sleep(1) # wait for the sniffer to start.
time.sleep(3) # wait for the sniffer to start.
# TODO: send intial first byte
# TODO: send intial first byte
send_initial_syn()
if __name__ == "__main__":
if __name__ == '__main__':
logging.basicConfig(
level=logging.INFO,
format="%(asctime)s %(levelname)s [%(module)s:%(lineno)d] %(message)s",
format='%(asctime)s %(levelname)s [%(module)s:%(lineno)d] %(message)s',
)
logging.getLogger("asyncio").setLevel(logging.WARNING)
logging.getLogger('asyncio').setLevel(logging.WARNING)
main()