// SPDX-License-Identifier: GPL-2.0-or-later
/*
* net/dccp/feat.c
*
* Feature negotiation for the DCCP protocol (RFC 4340, section 6)
*
* Copyright (c) 2008 Gerrit Renker <gerrit@erg.abdn.ac.uk>
* Rewrote from scratch, some bits from earlier code by
* Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk>
*
* ASSUMPTIONS
* -----------
* o Feature negotiation is coordinated with connection setup (as in TCP), wild
* changes of parameters of an established connection are not supported.
* o Changing non-negotiable (NN) values is supported in state OPEN/P