sys/linux/mptcp.txt

# Copyright 2018 syzkaller project authors. All rights reserved.
# # Use of this source code is governed by Apache 2 LICENSE that can be found in the LICENSE file.

# TCP Extensions for Multipath Operation with Multiple Addresses
# https://tools.ietf.org/html/rfc6824
# This is not upstream yes, constants for this descriptions were generated on the following tree:
# https://github.com/multipath-tcp/mptcp_net-next.git
# Once this is upstream we need to move this to vnet.txt

include <net/tcp.h>
include <net/mptcp.h>
include <net/mptcp_v4.h>
include <net/mptcp_v6.h>
include <uapi/linux/tcp.h>

tcp_mptcp_option [
	generic		mptcp_generic_option
	syn		mptcp_syn_option
	synack		mptcp_synack_option
	ack		mptcp_ack_option
	capable		mptcp_capable_option
	add_addr	mptcp_add_addr_option
	mp_join		mptcp_mp_join_option
	mp_fclose	mptcp_mp_fclose_option
	remove_addr	mptcp_remove_addr_option
] [varlen]

mptcp_sub_types = OPTION_TYPE_SYN, OPTION_TYPE_SYNACK, OPTION_TYPE_ACK, OPTION_MP_CAPABLE, OPTION_ADD_ADDR, OPTION_MP_JOIN, OPTION_MP_FCLOSE, OPTION_REMOVE_ADDR

mptcp_generic_option {
	type	flags[mptcp_sub_types, int8]
	length	len[parent, int8]
	data	array[int8, 0:16]
} [packed]

mptcp_capable_option {
	type		const[TCPOPT_MPTCP, int8]
	length		len[parent, int8]
	version		int8:4
	subtype		const[OPTION_MP_CAPABLE, int8:4]
	flags		int8
	sender		int64be
	receiver	array[int64be, 0:1]
} [packed]

mptcp_add_addr_option {
	type	const[TCPOPT_MPTCP, int8]
	length	len[parent, int8]
	subtype	const[OPTION_ADD_ADDR, int8:4]
	version	len[parent, int8:4]
	addr_id	int8
	address	ipv4_addr
	port	int16be
	mac	array[int8, 0:8]
} [packed]

mptcp_mp_join_option {
	type	const[TCPOPT_MPTCP, int8]
	length	len[parent, int8]
	flags	int8:4
	subtype	const[OPTION_MP_JOIN, int8:4]
} [packed]

mptcp_syn_option {
	type	const[TCPOPT_MPTCP, int8]
	length	len[parent, int8]
	flags	int8:4
	subtype	const[OPTION_TYPE_SYN, int8:4]
	addr_id	int8
	token	int32
	nonce	int32
} [packed]

mptcp_synack_option {
	type	const[TCPOPT_MPTCP, int8]
	length	len[parent, int8]
	flags	int8:4
	subtype	const[OPTION_TYPE_SYNACK, int8:4]
	addr_id	int8
	mac	int64
	nonce	int32
} [packed]

mptcp_ack_option {
	type		const[TCPOPT_MPTCP, int8]
	length		len[parent, int8]
	reserved	int16:12
	subtype		const[OPTION_TYPE_ACK, int16:4]
	mac		array[int8, 0:20]
} [packed]

mptcp_mp_fclose_option {
	type		const[TCPOPT_MPTCP, int8]
	length		len[parent, int8]
	reserved	int16:12
	subtype		const[OPTION_MP_FCLOSE, int16:4]
	key		int64
} [packed]

mptcp_remove_addr_option {
	type		const[TCPOPT_MPTCP, int8]
	length		len[parent, int8]
	reserved	int8:4
	subtype		const[OPTION_REMOVE_ADDR, int8:4]
	addrs_id	array[int8]
} [packed]