#include <net/if_arp.h>

net/if_arp.h

includes: stdint.h, sys/appleapiopts.h, netinet/in.h

16 macros · 3 structs

structarphdr

Address Resolution Protocol. See RFC 826 for protocol description. ARP packets are variable in size; the arphdr structure defines the fixed-length portion. Protocol type values are the same as those for 10 Mb/s Ethernet. It is followed by the variable-sized fields ar_sha, arp_spa, arp_tha and arp_tpa in that order, according to the lengths specified. Field names used correspond to RFC 826.

size 8, align 2

u_short	ar_hrd	format of hardware address
u_short	ar_pro	format of protocol address
u_char	ar_hln	length of hardware address
u_char	ar_pln	length of protocol address
u_short	ar_op	one of:

macroARPHRD_ETHER

#define ARPHRD_ETHER 1

ethernet hardware format

macroARPHRD_IEEE802

#define ARPHRD_IEEE802 6

token-ring hardware format

macroARPHRD_FRELAY

#define ARPHRD_FRELAY 15

frame relay hardware format

macroARPHRD_IEEE1394

#define ARPHRD_IEEE1394 24

IEEE1394 hardware address

macroARPHRD_IEEE1394_EUI64

#define ARPHRD_IEEE1394_EUI64 27

IEEE1394 EUI-64

macroARPOP_REQUEST

#define ARPOP_REQUEST 1

request to resolve address

macroARPOP_REPLY

#define ARPOP_REPLY 2

response to previous request

macroARPOP_REVREQUEST

#define ARPOP_REVREQUEST 3

request protocol address given hardware

macroARPOP_REVREPLY

#define ARPOP_REVREPLY 4

response giving protocol address

macroARPOP_INVREQUEST

#define ARPOP_INVREQUEST 8

request to identify peer

macroARPOP_INVREPLY

#define ARPOP_INVREPLY 9

response identifying peer

structarpreq

ARP ioctl request

size 36, align 4

struct sockaddr	arp_pa	protocol address
struct sockaddr	arp_ha	hardware address
int	arp_flags	flags

macroATF_INUSE

arp_flags and at_flags field values

#define ATF_INUSE 0x01

entry in use

macroATF_COM

#define ATF_COM 0x02

completed entry (enaddr valid)

macroATF_PERM

#define ATF_PERM 0x04

permanent entry

macroATF_PUBL

#define ATF_PUBL 0x08

publish entry (respond for other host)

macroATF_USETRAILERS

#define ATF_USETRAILERS 0x10

has requested trailers

structarpstat

size 64, align 4

uint32_t	txrequests	Normal things that happen: # of ARP requests sent by this host.
uint32_t	txreplies	# of ARP replies sent by this host.
uint32_t	txannounces	# of ARP announcements sent by this host.
uint32_t	rxrequests	# of ARP requests received by this host.
uint32_t	rxreplies	# of ARP replies received by this host.
uint32_t	received	# of ARP packets received by this host.
uint32_t	txconflicts	Abnormal event and error counting: # of ARP conflict probes sent
uint32_t	invalidreqs	# of invalid ARP resolve requests
uint32_t	reqnobufs	# of failed requests due to no memory
uint32_t	dropped	# of packets dropped waiting for a reply.
uint32_t	purged	# of packets purged while removing entries
uint32_t	timeouts	# of times with entries removed
uint32_t	dupips	due to timeout. # of duplicate IPs detected.
uint32_t	inuse	General statistics # of ARP entries in routing table
uint32_t	txurequests	# of ARP requests sent (unicast)
uint32_t	held	# of packets held waiting for a reply