freebsd-dev/sys/net/if_arp.h
Bjoern A. Zeeb b25d74e06c Improve ARP logging.
r344504 added an extra ARP_LOG() call in case of an if_output() failure.
It turns out IPv4 can be noisy. In order to not spam the console by default:
(a) add a counter for these events so people can keep better track of how
    often it happens, and
(b) add a sysctl to select the default ARP_LOG log level and set it to
    INFO avoiding the one (the new) DEBUG level by default.

Claim a spare (1st one after 10 years since the stats were added) in order
to not break netstat from FreeBSD 12->13 updates in the future.

Reviewed by:		karels
Differential Revision:	https://reviews.freebsd.org/D19490
2019-03-09 01:12:59 +00:00

136 lines
5.4 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1986, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)if_arp.h 8.1 (Berkeley) 6/10/93
* $FreeBSD$
*/
#ifndef _NET_IF_ARP_H_
#define _NET_IF_ARP_H_
/*
* 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.
*/
struct arphdr {
u_short ar_hrd; /* format of hardware address */
#define ARPHRD_ETHER 1 /* ethernet hardware format */
#define ARPHRD_IEEE802 6 /* token-ring hardware format */
#define ARPHRD_FRELAY 15 /* frame relay hardware format */
#define ARPHRD_IEEE1394 24 /* firewire hardware format */
#define ARPHRD_INFINIBAND 32 /* infiniband hardware format */
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: */
#define ARPOP_REQUEST 1 /* request to resolve address */
#define ARPOP_REPLY 2 /* response to previous request */
#define ARPOP_REVREQUEST 3 /* request protocol address given hardware */
#define ARPOP_REVREPLY 4 /* response giving protocol address */
#define ARPOP_INVREQUEST 8 /* request to identify peer */
#define ARPOP_INVREPLY 9 /* response identifying peer */
/*
* The remaining fields are variable in size,
* according to the sizes above.
*/
#ifdef COMMENT_ONLY
u_char ar_sha[]; /* sender hardware address */
u_char ar_spa[]; /* sender protocol address */
u_char ar_tha[]; /* target hardware address */
u_char ar_tpa[]; /* target protocol address */
#endif
};
#define ar_sha(ap) (((caddr_t)((ap)+1)) + 0)
#define ar_spa(ap) (((caddr_t)((ap)+1)) + (ap)->ar_hln)
#define ar_tha(ap) (((caddr_t)((ap)+1)) + (ap)->ar_hln + (ap)->ar_pln)
#define ar_tpa(ap) (((caddr_t)((ap)+1)) + 2*(ap)->ar_hln + (ap)->ar_pln)
#define arphdr_len2(ar_hln, ar_pln) \
(sizeof(struct arphdr) + 2*(ar_hln) + 2*(ar_pln))
#define arphdr_len(ap) (arphdr_len2((ap)->ar_hln, (ap)->ar_pln))
/*
* ARP ioctl request
*/
struct arpreq {
struct sockaddr arp_pa; /* protocol address */
struct sockaddr arp_ha; /* hardware address */
int arp_flags; /* flags */
};
/* arp_flags and at_flags field values */
#define ATF_INUSE 0x01 /* entry in use */
#define ATF_COM 0x02 /* completed entry (enaddr valid) */
#define ATF_PERM 0x04 /* permanent entry */
#define ATF_PUBL 0x08 /* publish entry (respond for other host) */
#define ATF_USETRAILERS 0x10 /* has requested trailers */
struct arpstat {
/* Normal things that happen: */
uint64_t txrequests; /* # of ARP requests sent by this host. */
uint64_t txreplies; /* # of ARP replies sent by this host. */
uint64_t rxrequests; /* # of ARP requests received by this host. */
uint64_t rxreplies; /* # of ARP replies received by this host. */
uint64_t received; /* # of ARP packets received by this host. */
uint64_t txerrors; /* # of ARP requests failed to send. */
uint64_t arp_spares[3]; /* For either the upper or lower half. */
/* Abnormal event and error counting: */
uint64_t dropped; /* # of packets dropped waiting for a reply. */
uint64_t timeouts; /* # of times with entries removed */
/* due to timeout. */
uint64_t dupips; /* # of duplicate IPs detected. */
};
#ifdef _KERNEL
#include <sys/counter.h>
#include <net/vnet.h>
VNET_PCPUSTAT_DECLARE(struct arpstat, arpstat);
/*
* In-kernel consumers can use these accessor macros directly to update
* stats.
*/
#define ARPSTAT_ADD(name, val) \
VNET_PCPUSTAT_ADD(struct arpstat, arpstat, name, (val))
#define ARPSTAT_SUB(name, val) ARPSTAT_ADD(name, -(val))
#define ARPSTAT_INC(name) ARPSTAT_ADD(name, 1)
#define ARPSTAT_DEC(name) ARPSTAT_SUB(name, 1)
#endif /* _KERNEL */
#endif /* !_NET_IF_ARP_H_ */