1/*
2 * INET		An implementation of the TCP/IP protocol suite for the LINUX
3 *		operating system.  INET is implemented using the  BSD Socket
4 *		interface as the means of communication with the user level.
5 *
6 *		Global definitions for the ARP (RFC 826) protocol.
7 *
8 * Version:	@(#)if_arp.h	1.0.1	04/16/93
9 *
10 * Authors:	Original taken from Berkeley UNIX 4.3, (c) UCB 1986-1988
11 *		Portions taken from the KA9Q/NOS (v2.00m PA0GRI) source.
12 *		Ross Biro
13 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
14 *		Florian La Roche,
15 *		Jonathan Layes <layes@loran.com>
16 *		Arnaldo Carvalho de Melo <acme@conectiva.com.br> ARPHRD_HWX25
17 *
18 *		This program is free software; you can redistribute it and/or
19 *		modify it under the terms of the GNU General Public License
20 *		as published by the Free Software Foundation; either version
21 *		2 of the License, or (at your option) any later version.
22 */
23#ifndef _LINUX_IF_ARP_H
24#define _LINUX_IF_ARP_H
25
26#include <linux/skbuff.h>
27#include <uapi/linux/if_arp.h>
28
29static inline struct arphdr *arp_hdr(const struct sk_buff *skb)
30{
31	return (struct arphdr *)skb_network_header(skb);
32}
33
34static inline int arp_hdr_len(struct net_device *dev)
35{
36	switch (dev->type) {
37#if IS_ENABLED(CONFIG_FIREWIRE_NET)
38	case ARPHRD_IEEE1394:
39		/* ARP header, device address and 2 IP addresses */
40		return sizeof(struct arphdr) + dev->addr_len + sizeof(u32) * 2;
41#endif
42	default:
43		/* ARP header, plus 2 device addresses, plus 2 IP addresses. */
44		return sizeof(struct arphdr) + (dev->addr_len + sizeof(u32)) * 2;
45	}
46}
47#endif	/* _LINUX_IF_ARP_H */
48