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telnet: strip IAC command sequences
+28
-1
+28
-1
telnet/server.py
+28
-1
telnet/server.py
···
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return "\r\n".join(out)
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def strip_iac(data: bytes) -> bytes:
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"""Strip telnet IAC command sequences from raw bytes."""
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out = bytearray()
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i = 0
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while i < len(data):
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if data[i] == 0xFF and i + 1 < len(data):
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cmd = data[i + 1]
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if cmd == 0xFF:
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out.append(0xFF)
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i += 2
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elif cmd in (0xFB, 0xFC, 0xFD, 0xFE):
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i += 3 # WILL/WONT/DO/DONT + option
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elif cmd == 0xFA:
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i += 2 # sub-negotiation: skip until IAC SE
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while i < len(data):
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if data[i] == 0xFF and i + 1 < len(data) and data[i + 1] == 0xF0:
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i += 2
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break
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i += 1
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else:
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i += 2
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else:
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out.append(data[i])
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i += 1
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return bytes(out)
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+
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async def write(writer: asyncio.StreamWriter, text: str):
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writer.write(wrap(text).encode())
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await writer.drain()
···
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return ""
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if not data:
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return ""
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text = data.decode(errors="ignore").strip()
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text = strip_iac(data).decode(errors="ignore").strip()
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return re.sub(r"[^\x20-\x7e]", "", text)
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