35 lines
1.1 KiB
Python
35 lines
1.1 KiB
Python
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#!/usr/bin/env python3
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"""Strip IP+UDP headers from mirrored packets and forward raw UDP payload."""
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import socket
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import sys
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LISTEN_PORT = int(sys.argv[1]) if len(sys.argv) > 1 else 9100
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FORWARD_HOST = sys.argv[2] if len(sys.argv) > 2 else "127.0.0.1"
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FORWARD_PORT = int(sys.argv[3]) if len(sys.argv) > 3 else 9000
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sock_in = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
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sock_in.bind(("0.0.0.0", LISTEN_PORT))
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sock_out = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
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count = 0
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while True:
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data, addr = sock_in.recvfrom(65535)
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if len(data) < 28:
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continue
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# IP header: first nibble is version (4), second nibble is IHL (words)
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if (data[0] >> 4) != 4:
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continue
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ihl = (data[0] & 0x0F) * 4
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# Protocol should be UDP (17)
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if data[9] != 17:
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continue
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# Payload starts after IP header + 8-byte UDP header
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offset = ihl + 8
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payload = data[offset:]
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if payload:
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sock_out.sendto(payload, (FORWARD_HOST, FORWARD_PORT))
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count += 1
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if count % 10000 == 0:
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print(f"Forwarded {count} shreds", flush=True)
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