Gecko [ www.jobworksschool.com ]

Name	Size	Permission	Date
9p	[ DIR ]	drwxr-xr-x	2026-07-17 06:29
bluetooth	[ DIR ]	drwxr-xr-x	2026-07-17 06:29
caif	[ DIR ]	drwxr-xr-x	2026-07-17 06:29
iucv	[ DIR ]	drwxr-xr-x	2026-07-17 06:29
mana	[ DIR ]	drwxr-xr-x	2026-07-17 06:29
netfilter	[ DIR ]	drwxr-xr-x	2026-07-17 06:29
netns	[ DIR ]	drwxr-xr-x	2026-07-17 06:29
nfc	[ DIR ]	drwxr-xr-x	2026-07-17 06:29
page_pool	[ DIR ]	drwxr-xr-x	2026-07-17 06:29
phonet	[ DIR ]	drwxr-xr-x	2026-07-17 06:29
sctp	[ DIR ]	drwxr-xr-x	2026-07-17 06:29
tc_act	[ DIR ]	drwxr-xr-x	2026-07-17 06:29
6lowpan.h	10.03 KB	-rw-r--r--	2024-03-10 20:38
Space.h	455 B	-rw-r--r--	2024-03-10 20:38
act_api.h	9.35 KB	-rw-r--r--	2026-07-01 19:48
addrconf.h	14.28 KB	-rw-r--r--	2026-07-01 19:48
af_ieee802154.h	1.19 KB	-rw-r--r--	2024-03-10 20:38
af_rxrpc.h	3.3 KB	-rw-r--r--	2024-03-10 20:38
af_unix.h	3.76 KB	-rw-r--r--	2026-07-01 19:48
af_vsock.h	8.41 KB	-rw-r--r--	2026-07-01 19:48
ah.h	382 B	-rw-r--r--	2024-03-10 20:38
amt.h	8.35 KB	-rw-r--r--	2024-03-10 20:38
arp.h	1.95 KB	-rw-r--r--	2024-03-10 20:38
atmclip.h	1.48 KB	-rw-r--r--	2024-03-10 20:38
ax25.h	14.94 KB	-rw-r--r--	2026-07-01 19:48
ax88796.h	1.43 KB	-rw-r--r--	2024-03-10 20:38
bareudp.h	333 B	-rw-r--r--	2024-03-10 20:38
bond_3ad.h	9.5 KB	-rw-r--r--	2026-07-01 19:48
bond_alb.h	6.1 KB	-rw-r--r--	2024-03-10 20:38
bond_options.h	4.88 KB	-rw-r--r--	2026-07-01 19:48
bonding.h	21.5 KB	-rw-r--r--	2026-07-01 19:48
bpf_sk_storage.h	1.74 KB	-rw-r--r--	2024-03-10 20:38
busy_poll.h	4.28 KB	-rw-r--r--	2026-07-01 19:48
calipso.h	1.55 KB	-rw-r--r--	2024-03-10 20:38
cfg80211-wext.h	1.86 KB	-rw-r--r--	2024-03-10 20:38
cfg80211.h	336.64 KB	-rw-r--r--	2026-07-01 19:48
cfg802154.h	16.68 KB	-rw-r--r--	2026-07-01 19:48
checksum.h	4.98 KB	-rw-r--r--	2026-07-01 19:48
cipso_ipv4.h	7.37 KB	-rw-r--r--	2024-03-10 20:38
cls_cgroup.h	2.04 KB	-rw-r--r--	2026-07-01 19:48
codel.h	5.86 KB	-rw-r--r--	2024-03-10 20:38
codel_impl.h	8.3 KB	-rw-r--r--	2024-03-10 20:38
codel_qdisc.h	2.95 KB	-rw-r--r--	2024-03-10 20:38
compat.h	2.48 KB	-rw-r--r--	2024-03-10 20:38
datalink.h	590 B	-rw-r--r--	2024-03-10 20:38
dcbevent.h	766 B	-rw-r--r--	2024-03-10 20:38
dcbnl.h	4.98 KB	-rw-r--r--	2024-03-10 20:38
devlink.h	70.92 KB	-rw-r--r--	2024-03-10 20:38
dropreason-core.h	14.76 KB	-rw-r--r--	2026-07-01 19:48
dropreason.h	1.36 KB	-rw-r--r--	2024-03-10 20:38
dsa.h	41.09 KB	-rw-r--r--	2026-07-01 19:48
dsa_stubs.h	1.28 KB	-rw-r--r--	2024-03-10 20:38
dsfield.h	1.12 KB	-rw-r--r--	2024-03-10 20:38
dst.h	15.12 KB	-rw-r--r--	2026-07-01 19:48
dst_cache.h	2.96 KB	-rw-r--r--	2024-03-10 20:38
dst_metadata.h	6.34 KB	-rw-r--r--	2024-03-10 20:38
dst_ops.h	2.07 KB	-rw-r--r--	2026-07-01 19:48
erspan.h	9.04 KB	-rw-r--r--	2024-03-10 20:38
esp.h	1.18 KB	-rw-r--r--	2024-03-10 20:38
espintcp.h	966 B	-rw-r--r--	2024-03-10 20:38
ethoc.h	439 B	-rw-r--r--	2024-03-10 20:38
failover.h	1.18 KB	-rw-r--r--	2024-03-10 20:38
fib_notifier.h	1.35 KB	-rw-r--r--	2024-03-10 20:38
fib_rules.h	5.39 KB	-rw-r--r--	2024-03-10 20:38
firewire.h	599 B	-rw-r--r--	2024-03-10 20:38
flow.h	4.96 KB	-rw-r--r--	2024-03-10 20:38
flow_dissector.h	11.95 KB	-rw-r--r--	2024-03-10 20:38
flow_offload.h	17.37 KB	-rw-r--r--	2024-03-10 20:38
fou.h	578 B	-rw-r--r--	2024-03-10 20:38
fq.h	2.41 KB	-rw-r--r--	2024-03-10 20:38
fq_impl.h	7.96 KB	-rw-r--r--	2024-03-10 20:38
garp.h	2.67 KB	-rw-r--r--	2024-03-10 20:38
gen_stats.h	2.99 KB	-rw-r--r--	2024-03-10 20:38
genetlink.h	19.62 KB	-rw-r--r--	2026-07-01 19:48
geneve.h	1.84 KB	-rw-r--r--	2024-03-10 20:38
gre.h	3.29 KB	-rw-r--r--	2024-03-10 20:38
gro.h	13.38 KB	-rw-r--r--	2026-07-01 19:48
gro_cells.h	443 B	-rw-r--r--	2024-03-10 20:38
gso.h	3.2 KB	-rw-r--r--	2024-03-10 20:38
gtp.h	1.46 KB	-rw-r--r--	2024-03-10 20:38
gue.h	3.29 KB	-rw-r--r--	2024-03-10 20:38
handshake.h	1.39 KB	-rw-r--r--	2024-03-10 20:38
hwbm.h	995 B	-rw-r--r--	2024-03-10 20:38
icmp.h	1.87 KB	-rw-r--r--	2024-03-10 20:38
ieee80211_radiotap.h	23.22 KB	-rw-r--r--	2026-07-01 19:48
ieee802154_netdev.h	13.02 KB	-rw-r--r--	2024-03-10 20:38
if_inet6.h	6.6 KB	-rw-r--r--	2024-03-10 20:38
ife.h	1.03 KB	-rw-r--r--	2024-03-10 20:38
inet6_connection_sock.h	794 B	-rw-r--r--	2024-03-10 20:38
inet6_hashtables.h	5.57 KB	-rw-r--r--	2026-07-01 19:48
inet_common.h	2.83 KB	-rw-r--r--	2024-03-10 20:38
inet_connection_sock.h	11.7 KB	-rw-r--r--	2026-07-01 19:48
inet_dscp.h	1.55 KB	-rw-r--r--	2024-03-10 20:38
inet_ecn.h	7.83 KB	-rw-r--r--	2024-03-10 20:38
inet_frag.h	5.25 KB	-rw-r--r--	2026-07-01 19:48
inet_hashtables.h	16.91 KB	-rw-r--r--	2026-07-01 19:48
inet_sock.h	11.36 KB	-rw-r--r--	2026-07-01 19:48
inet_timewait_sock.h	3.71 KB	-rw-r--r--	2026-07-01 19:48
inetpeer.h	3.23 KB	-rw-r--r--	2026-07-01 19:48
ioam6.h	1.24 KB	-rw-r--r--	2026-07-01 19:48
ip.h	23.13 KB	-rw-r--r--	2026-07-01 19:48
ip6_checksum.h	2.3 KB	-rw-r--r--	2024-03-10 20:38
ip6_fib.h	17.6 KB	-rw-r--r--	2026-07-01 19:48
ip6_route.h	10.18 KB	-rw-r--r--	2026-07-01 19:48
ip6_tunnel.h	5.31 KB	-rw-r--r--	2026-07-01 19:48
ip_fib.h	16.13 KB	-rw-r--r--	2026-07-01 19:48
ip_tunnels.h	16.89 KB	-rw-r--r--	2026-07-01 19:48
ip_vs.h	53.83 KB	-rw-r--r--	2024-03-10 20:38
ipcomp.h	737 B	-rw-r--r--	2024-03-10 20:38
ipconfig.h	837 B	-rw-r--r--	2024-03-10 20:38
ipv6.h	37.62 KB	-rw-r--r--	2026-07-01 19:48
ipv6_frag.h	3.38 KB	-rw-r--r--	2024-03-10 20:38
ipv6_stubs.h	3.75 KB	-rw-r--r--	2026-07-01 19:48
iw_handler.h	20.66 KB	-rw-r--r--	2024-03-10 20:38
kcm.h	4.84 KB	-rw-r--r--	2026-07-01 19:48
l3mdev.h	7.03 KB	-rw-r--r--	2026-07-01 19:48
lag.h	409 B	-rw-r--r--	2024-03-10 20:38
lapb.h	4.82 KB	-rw-r--r--	2026-07-01 19:48
lib80211.h	3.92 KB	-rw-r--r--	2024-03-10 20:38
llc.h	4.41 KB	-rw-r--r--	2024-03-10 20:38
llc_c_ac.h	9.32 KB	-rw-r--r--	2024-03-10 20:38
llc_c_ev.h	10.61 KB	-rw-r--r--	2024-03-10 20:38
llc_c_st.h	1.77 KB	-rw-r--r--	2024-03-10 20:38
llc_conn.h	4.11 KB	-rw-r--r--	2024-03-10 20:38
llc_if.h	2.17 KB	-rw-r--r--	2024-03-10 20:38
llc_pdu.h	14.46 KB	-rw-r--r--	2024-03-10 20:38
llc_s_ac.h	1.59 KB	-rw-r--r--	2024-03-10 20:38
llc_s_ev.h	2.22 KB	-rw-r--r--	2024-03-10 20:38
llc_s_st.h	1.03 KB	-rw-r--r--	2024-03-10 20:38
llc_sap.h	1.08 KB	-rw-r--r--	2024-03-10 20:38
lwtunnel.h	6.69 KB	-rw-r--r--	2026-07-01 19:48
mac80211.h	293.31 KB	-rw-r--r--	2026-07-01 19:48
mac802154.h	14.88 KB	-rw-r--r--	2024-03-10 20:38
macsec.h	10.53 KB	-rw-r--r--	2026-07-01 19:48
mctp.h	8.1 KB	-rw-r--r--	2026-07-01 19:48
mctpdevice.h	1.26 KB	-rw-r--r--	2024-03-10 20:38
mip6.h	1016 B	-rw-r--r--	2024-03-10 20:38
mld.h	2.85 KB	-rw-r--r--	2024-03-10 20:38
mpls.h	943 B	-rw-r--r--	2024-03-10 20:38
mpls_iptunnel.h	481 B	-rw-r--r--	2024-03-10 20:38
mptcp.h	7.41 KB	-rw-r--r--	2024-03-10 20:38
mrp.h	3.13 KB	-rw-r--r--	2024-03-10 20:38
ncsi.h	1.94 KB	-rw-r--r--	2024-03-10 20:38
ndisc.h	14.64 KB	-rw-r--r--	2024-03-10 20:38
neighbour.h	16.55 KB	-rw-r--r--	2026-07-01 19:48
net_debug.h	5.08 KB	-rw-r--r--	2026-07-01 19:48
net_failover.h	1023 B	-rw-r--r--	2024-03-10 20:38
net_namespace.h	14.36 KB	-rw-r--r--	2026-07-01 19:48
net_ratelimit.h	220 B	-rw-r--r--	2024-03-10 20:38
net_trackers.h	424 B	-rw-r--r--	2024-03-10 20:38
netdev_queues.h	5.75 KB	-rw-r--r--	2024-03-10 20:38
netdev_rx_queue.h	1.32 KB	-rw-r--r--	2024-03-10 20:38
netevent.h	1.04 KB	-rw-r--r--	2024-03-10 20:38
netkit.h	1.16 KB	-rw-r--r--	2024-03-10 20:38
netlabel.h	20.15 KB	-rw-r--r--	2026-07-01 19:48
netlink.h	64.18 KB	-rw-r--r--	2024-03-10 20:38
netprio_cgroup.h	1.02 KB	-rw-r--r--	2024-03-10 20:38
netrom.h	7.73 KB	-rw-r--r--	2024-03-10 20:38
nexthop.h	11.91 KB	-rw-r--r--	2024-03-10 20:38
nl802154.h	16.04 KB	-rw-r--r--	2024-03-10 20:38
nsh.h	12.3 KB	-rw-r--r--	2024-03-10 20:38
p8022.h	403 B	-rw-r--r--	2024-03-10 20:38
pie.h	3.61 KB	-rw-r--r--	2026-07-01 19:48
ping.h	2.66 KB	-rw-r--r--	2024-03-10 20:38
pkt_cls.h	25.52 KB	-rw-r--r--	2026-07-01 19:48
pkt_sched.h	7.74 KB	-rw-r--r--	2026-07-01 19:48
pptp.h	604 B	-rw-r--r--	2024-03-10 20:38
protocol.h	3.81 KB	-rw-r--r--	2024-03-10 20:38
psample.h	1.06 KB	-rw-r--r--	2024-03-10 20:38
psnap.h	430 B	-rw-r--r--	2024-03-10 20:38
raw.h	2.46 KB	-rw-r--r--	2024-03-10 20:38
rawv6.h	862 B	-rw-r--r--	2024-03-10 20:38
red.h	11.33 KB	-rw-r--r--	2024-03-10 20:38
regulatory.h	9.96 KB	-rw-r--r--	2024-03-10 20:38
request_sock.h	6.5 KB	-rw-r--r--	2024-03-10 20:38
rose.h	8.06 KB	-rw-r--r--	2026-07-01 19:48
route.h	11.32 KB	-rw-r--r--	2026-07-01 19:48
rpl.h	749 B	-rw-r--r--	2024-03-10 20:38
rsi_91x.h	1.67 KB	-rw-r--r--	2024-03-10 20:38
rtnetlink.h	7.58 KB	-rw-r--r--	2026-07-01 19:48
rtnh.h	859 B	-rw-r--r--	2024-03-10 20:38
sch_generic.h	35.08 KB	-rw-r--r--	2026-07-01 19:48
scm.h	5.36 KB	-rw-r--r--	2026-07-01 19:48
secure_seq.h	868 B	-rw-r--r--	2024-03-10 20:38
seg6.h	2.18 KB	-rw-r--r--	2024-03-10 20:38
seg6_hmac.h	1.44 KB	-rw-r--r--	2024-03-10 20:38
seg6_local.h	644 B	-rw-r--r--	2024-03-10 20:38
selftests.h	582 B	-rw-r--r--	2024-03-10 20:38
slhc_vj.h	6.67 KB	-rw-r--r--	2024-03-10 20:38
smc.h	2.5 KB	-rw-r--r--	2026-07-01 19:48
snmp.h	5.14 KB	-rw-r--r--	2024-03-10 20:38
sock.h	85.78 KB	-rw-r--r--	2026-07-01 19:48
sock_reuseport.h	1.83 KB	-rw-r--r--	2024-03-10 20:38
stp.h	412 B	-rw-r--r--	2024-03-10 20:38
strparser.h	4.34 KB	-rw-r--r--	2026-07-01 19:48
switchdev.h	15.1 KB	-rw-r--r--	2024-03-10 20:38
tc_wrapper.h	6.29 KB	-rw-r--r--	2026-07-01 19:48
tcp.h	85.12 KB	-rw-r--r--	2026-07-01 19:48
tcp_ao.h	12.08 KB	-rw-r--r--	2026-07-01 19:48
tcp_states.h	1.3 KB	-rw-r--r--	2024-03-10 20:38
tcx.h	4.3 KB	-rw-r--r--	2026-07-01 19:48
timewait_sock.h	925 B	-rw-r--r--	2024-03-10 20:38
tipc.h	2.35 KB	-rw-r--r--	2024-03-10 20:38
tls.h	13.28 KB	-rw-r--r--	2026-07-01 19:48
tls_prot.h	1.84 KB	-rw-r--r--	2024-03-10 20:38
tls_toe.h	2.94 KB	-rw-r--r--	2024-03-10 20:38
transp_v6.h	1.88 KB	-rw-r--r--	2024-03-10 20:38
tso.h	721 B	-rw-r--r--	2024-03-10 20:38
tun_proto.h	1015 B	-rw-r--r--	2024-03-10 20:38
udp.h	15.88 KB	-rw-r--r--	2026-07-01 19:48
udp_tunnel.h	12.49 KB	-rw-r--r--	2026-07-01 19:48
udplite.h	2.3 KB	-rw-r--r--	2024-03-10 20:38
vsock_addr.h	662 B	-rw-r--r--	2024-03-10 20:38
vxlan.h	15.83 KB	-rw-r--r--	2026-07-01 19:48
wext.h	1.47 KB	-rw-r--r--	2024-03-10 20:38
x25.h	9.46 KB	-rw-r--r--	2024-03-10 20:38
x25device.h	387 B	-rw-r--r--	2024-03-10 20:38
xdp.h	16.93 KB	-rw-r--r--	2026-07-01 19:48
xdp_priv.h	427 B	-rw-r--r--	2024-03-10 20:38
xdp_sock.h	6.3 KB	-rw-r--r--	2026-07-01 19:48
xdp_sock_drv.h	10.15 KB	-rw-r--r--	2026-07-01 19:48
xfrm.h	58.29 KB	-rw-r--r--	2026-07-01 19:48
xsk_buff_pool.h	7.09 KB	-rw-r--r--	2026-07-01 19:48

Rename

/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Management Component Transport Protocol (MCTP)
 *
 * Copyright (c) 2021 Code Construct
 * Copyright (c) 2021 Google
 */

#ifndef __NET_MCTP_H
#define __NET_MCTP_H

#include <linux/bits.h>
#include <linux/mctp.h>
#include <linux/netdevice.h>
#include <net/net_namespace.h>
#include <net/sock.h>

/* MCTP packet definitions */
struct mctp_hdr {
	u8	ver;
	u8	dest;
	u8	src;
	u8	flags_seq_tag;
};

#define MCTP_VER_MIN	1
#define MCTP_VER_MAX	1

/* Definitions for ver field */
#define MCTP_HDR_VER_MASK	GENMASK(3, 0)

/* Definitions for flags_seq_tag field */
#define MCTP_HDR_FLAG_SOM	BIT(7)
#define MCTP_HDR_FLAG_EOM	BIT(6)
#define MCTP_HDR_FLAG_TO	BIT(3)
#define MCTP_HDR_FLAGS		GENMASK(5, 3)
#define MCTP_HDR_SEQ_SHIFT	4
#define MCTP_HDR_SEQ_MASK	GENMASK(1, 0)
#define MCTP_HDR_TAG_SHIFT	0
#define MCTP_HDR_TAG_MASK	GENMASK(2, 0)

#define MCTP_INITIAL_DEFAULT_NET	1

static inline bool mctp_address_unicast(mctp_eid_t eid)
{
	return eid >= 8 && eid < 255;
}

static inline bool mctp_address_broadcast(mctp_eid_t eid)
{
	return eid == 255;
}

static inline bool mctp_address_null(mctp_eid_t eid)
{
	return eid == 0;
}

static inline bool mctp_address_matches(mctp_eid_t match, mctp_eid_t eid)
{
	return match == eid || match == MCTP_ADDR_ANY;
}

static inline struct mctp_hdr *mctp_hdr(struct sk_buff *skb)
{
	return (struct mctp_hdr *)skb_network_header(skb);
}

/* socket implementation */
struct mctp_sock {
	struct sock	sk;

/* bind() params */
	unsigned int	bind_net;
	mctp_eid_t	bind_addr;
	__u8		bind_type;

/* sendmsg()/recvmsg() uses struct sockaddr_mctp_ext */
	bool		addr_ext;

/* list of mctp_sk_key, for incoming tag lookup. updates protected
	 * by sk->net->keys_lock
	 */
	struct hlist_head keys;

/* mechanism for expiring allocated keys; will release an allocated
	 * tag, and any netdev state for a request/response pairing
	 */
	struct timer_list key_expiry;
};

/* Key for matching incoming packets to sockets or reassembly contexts.
 * Packets are matched on (src,dest,tag).
 *
 * Lifetime / locking requirements:
 *
 *  - individual key data (ie, the struct itself) is protected by key->lock;
 *    changes must be made with that lock held.
 *
 *  - the lookup fields: peer_addr, local_addr and tag are set before the
 *    key is added to lookup lists, and never updated.
 *
 *  - A ref to the key must be held (throuh key->refs) if a pointer to the
 *    key is to be accessed after key->lock is released.
 *
 *  - a mctp_sk_key contains a reference to a struct sock; this is valid
 *    for the life of the key. On sock destruction (through unhash), the key is
 *    removed from lists (see below), and marked invalid.
 *
 * - these mctp_sk_keys appear on two lists:
 *     1) the struct mctp_sock->keys list
 *     2) the struct netns_mctp->keys list
 *
 *   presences on these lists requires a (single) refcount to be held; both
 *   lists are updated as a single operation.
 *
 *   Updates and lookups in either list are performed under the
 *   netns_mctp->keys lock. Lookup functions will need to lock the key and
 *   take a reference before unlocking the keys_lock. Consequently, the list's
 *   keys_lock *cannot* be acquired with the individual key->lock held.
 *
 * - a key may have a sk_buff attached as part of an in-progress message
 *   reassembly (->reasm_head). The reasm data is protected by the individual
 *   key->lock.
 *
 * - there are two destruction paths for a mctp_sk_key:
 *
 *    - through socket unhash (see mctp_sk_unhash). This performs the list
 *      removal under keys_lock.
 *
 *    - where a key is established to receive a reply message: after receiving
 *      the (complete) reply, or during reassembly errors. Here, we clean up
 *      the reassembly context (marking reasm_dead, to prevent another from
 *      starting), and remove the socket from the netns & socket lists.
 *
 *    - through an expiry timeout, on a per-socket timer
 */
struct mctp_sk_key {
	mctp_eid_t	peer_addr;
	mctp_eid_t	local_addr; /* MCTP_ADDR_ANY for local owned tags */
	__u8		tag; /* incoming tag match; invert TO for local */

/* we hold a ref to sk when set */
	struct sock	*sk;

/* routing lookup list */
	struct hlist_node hlist;

/* per-socket list */
	struct hlist_node sklist;

/* lock protects against concurrent updates to the reassembly and
	 * expiry data below.
	 */
	spinlock_t	lock;

/* Keys are referenced during the output path, which may sleep */
	refcount_t	refs;

/* incoming fragment reassembly context */
	struct sk_buff	*reasm_head;
	struct sk_buff	**reasm_tailp;
	bool		reasm_dead;
	u8		last_seq;

/* key validity */
	bool		valid;

/* expiry timeout; valid (above) cleared on expiry */
	unsigned long	expiry;

/* free to use for device flow state tracking. Initialised to
	 * zero on initial key creation
	 */
	unsigned long	dev_flow_state;
	struct mctp_dev	*dev;

/* a tag allocated with SIOCMCTPALLOCTAG ioctl will not expire
	 * automatically on timeout or response, instead SIOCMCTPDROPTAG
	 * is used.
	 */
	bool		manual_alloc;
};

struct mctp_skb_cb {
	unsigned int	magic;
	unsigned int	net;
	int		ifindex; /* extended/direct addressing if set */
	mctp_eid_t	src;
	unsigned char	halen;
	unsigned char	haddr[MAX_ADDR_LEN];
};

/* skb control-block accessors with a little extra debugging for initial
 * development.
 *
 * TODO: remove checks & mctp_skb_cb->magic; replace callers of __mctp_cb
 * with mctp_cb().
 *
 * __mctp_cb() is only for the initial ingress code; we should see ->magic set
 * at all times after this.
 */
static inline struct mctp_skb_cb *__mctp_cb(struct sk_buff *skb)
{
	struct mctp_skb_cb *cb = (void *)skb->cb;

cb->magic = 0x4d435450;
	return cb;
}

static inline struct mctp_skb_cb *mctp_cb(struct sk_buff *skb)
{
	struct mctp_skb_cb *cb = (void *)skb->cb;

BUILD_BUG_ON(sizeof(struct mctp_skb_cb) > sizeof(skb->cb));
	WARN_ON(cb->magic != 0x4d435450);
	return (void *)(skb->cb);
}

/* If CONFIG_MCTP_FLOWS, we may add one of these as a SKB extension,
 * indicating the flow to the device driver.
 */
struct mctp_flow {
	struct mctp_sk_key *key;
};

/* Route definition.
 *
 * These are held in the pernet->mctp.routes list, with RCU protection for
 * removed routes. We hold a reference to the netdev; routes need to be
 * dropped on NETDEV_UNREGISTER events.
 *
 * Updates to the route table are performed under rtnl; all reads under RCU,
 * so routes cannot be referenced over a RCU grace period. Specifically: A
 * caller cannot block between mctp_route_lookup and mctp_route_release()
 */
struct mctp_route {
	mctp_eid_t		min, max;

unsigned char		type;
	unsigned int		mtu;
	struct mctp_dev		*dev;
	int			(*output)(struct mctp_route *route,
					  struct sk_buff *skb);

struct list_head	list;
	refcount_t		refs;
	struct rcu_head		rcu;
};

/* route interfaces */
struct mctp_route *mctp_route_lookup(struct net *net, unsigned int dnet,
				     mctp_eid_t daddr);

/* always takes ownership of skb */
int mctp_local_output(struct sock *sk, struct mctp_route *rt,
		      struct sk_buff *skb, mctp_eid_t daddr, u8 req_tag);

void mctp_key_unref(struct mctp_sk_key *key);
struct mctp_sk_key *mctp_alloc_local_tag(struct mctp_sock *msk,
					 mctp_eid_t daddr, mctp_eid_t saddr,
					 bool manual, u8 *tagp);

/* routing <--> device interface */
unsigned int mctp_default_net(struct net *net);
int mctp_default_net_set(struct net *net, unsigned int index);
int mctp_route_add_local(struct mctp_dev *mdev, mctp_eid_t addr);
int mctp_route_remove_local(struct mctp_dev *mdev, mctp_eid_t addr);
void mctp_route_remove_dev(struct mctp_dev *mdev);

/* neighbour definitions */
enum mctp_neigh_source {
	MCTP_NEIGH_STATIC,
	MCTP_NEIGH_DISCOVER,
};

struct mctp_neigh {
	struct mctp_dev		*dev;
	mctp_eid_t		eid;
	enum mctp_neigh_source	source;

unsigned char		ha[MAX_ADDR_LEN];

struct list_head	list;
	struct rcu_head		rcu;
};

int mctp_neigh_init(void);
void mctp_neigh_exit(void);

// ret_hwaddr may be NULL, otherwise must have space for MAX_ADDR_LEN
int mctp_neigh_lookup(struct mctp_dev *dev, mctp_eid_t eid,
		      void *ret_hwaddr);
void mctp_neigh_remove_dev(struct mctp_dev *mdev);

int mctp_routes_init(void);
void mctp_routes_exit(void);

int mctp_device_init(void);
void mctp_device_exit(void);

#endif /* __NET_MCTP_H */