linux-stable/include/linux/if_arp.h
Alexey Dobriyan 6ade97da60 arp: make arp_hdr_len() return unsigned int
Negative ARP header length are not a thing.

Constify arguments while I'm at it.

Space savings:

	add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-3 (-3)
	function                        old     new   delta
	arpt_do_table                  1163    1160      -3

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-28 10:29:36 -07:00

63 lines
1.8 KiB
C

/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* Global definitions for the ARP (RFC 826) protocol.
*
* Version: @(#)if_arp.h 1.0.1 04/16/93
*
* Authors: Original taken from Berkeley UNIX 4.3, (c) UCB 1986-1988
* Portions taken from the KA9Q/NOS (v2.00m PA0GRI) source.
* Ross Biro
* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
* Florian La Roche,
* Jonathan Layes <layes@loran.com>
* Arnaldo Carvalho de Melo <acme@conectiva.com.br> ARPHRD_HWX25
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#ifndef _LINUX_IF_ARP_H
#define _LINUX_IF_ARP_H
#include <linux/skbuff.h>
#include <uapi/linux/if_arp.h>
static inline struct arphdr *arp_hdr(const struct sk_buff *skb)
{
return (struct arphdr *)skb_network_header(skb);
}
static inline unsigned int arp_hdr_len(const struct net_device *dev)
{
switch (dev->type) {
#if IS_ENABLED(CONFIG_FIREWIRE_NET)
case ARPHRD_IEEE1394:
/* ARP header, device address and 2 IP addresses */
return sizeof(struct arphdr) + dev->addr_len + sizeof(u32) * 2;
#endif
default:
/* ARP header, plus 2 device addresses, plus 2 IP addresses. */
return sizeof(struct arphdr) + (dev->addr_len + sizeof(u32)) * 2;
}
}
static inline bool dev_is_mac_header_xmit(const struct net_device *dev)
{
switch (dev->type) {
case ARPHRD_TUNNEL:
case ARPHRD_TUNNEL6:
case ARPHRD_SIT:
case ARPHRD_IPGRE:
case ARPHRD_VOID:
case ARPHRD_NONE:
return false;
default:
return true;
}
}
#endif /* _LINUX_IF_ARP_H */