55 lines
1.0 KiB
Python
55 lines
1.0 KiB
Python
#!/usr/bin/env python3
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"""Minimal NFQUEUE example: add random delay and jitter, but do not drop packets."""
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import random
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import signal
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import sys
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import time
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from netfilterqueue import NetfilterQueue
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# Demo tuning values.
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BASE_DELAY_MS = 40
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JITTER_MS = 120
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nfq = NetfilterQueue()
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def _handle_packet(packet) -> None:
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delay_ms = BASE_DELAY_MS + random.uniform(0, JITTER_MS)
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time.sleep(delay_ms / 1000.0)
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packet.accept()
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def _stop(_sig, _frame) -> None:
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raise SystemExit(0)
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def main() -> int:
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if len(sys.argv) != 2:
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print("Usage: chaos_delay_jitter.py <qnum>", file=sys.stderr)
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return 1
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try:
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qnum = int(sys.argv[1])
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except ValueError:
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print("qnum must be an integer", file=sys.stderr)
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return 1
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signal.signal(signal.SIGINT, _stop)
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signal.signal(signal.SIGTERM, _stop)
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nfq.bind(qnum, _handle_packet)
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try:
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nfq.run()
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except KeyboardInterrupt:
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pass
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finally:
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nfq.unbind()
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return 0
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if __name__ == "__main__":
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raise SystemExit(main())
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