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ntunnel.py

@@ -155,6 +155,11 @@ async def NoiseForwarder(mode, rdrwrr, ptpair, priv_key, pub_key=None):
 		raise RuntimeError('failed to finish handshake')
 
 	# generate the keys for lengths
+	# XXX - get_handshake_hash is probably not the best option, but
+	# this is only to obscure lengths, it is not required to be secure
+	# as the underlying NoiseProtocol securely validates everything.
+	# It is marginally useful as writing patterns likely expose the
+	# true length.  Adding padding could marginally help w/ this.
 	if mode == 'resp':
 		_, declenfun = _genciphfun(proto.get_handshake_hash(), b'toresp')
 		enclenfun, _ = _genciphfun(proto.get_handshake_hash(), b'toinit')