include/linux/if_arp.h

   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
  29 static inline struct arphdr *arp_hdr(const struct sk_buff *skb)
  30 {
  31         return (struct arphdr *)skb_network_header(skb);
  32 }
  33
  34 static 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
  48 static inline bool dev_is_mac_header_xmit(const struct net_device *dev)
  49 {
  50         switch (dev->type) {
  51         case ARPHRD_TUNNEL:
  52         case ARPHRD_TUNNEL6:
  53         case ARPHRD_SIT:
  54         case ARPHRD_IPGRE:
  55         case ARPHRD_VOID:
  56         case ARPHRD_NONE:
  57                 return false;
  58         default:
  59                 return true;
  60         }
  61 }
  62
  63 #endif  /* _LINUX_IF_ARP_H */