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This library is stripped down version of NetServices library. HTTP server and client function is NOT supported.

lwip/netif/etharp.c@0:dcf3c92487ca, 2011-07-20 (annotated)

Committer:: idinor
Date:: Wed Jul 20 11:45:39 2011 +0000
Revision:: 0:dcf3c92487ca

Who changed what in which revision?

User	Revision	Line number	New contents of line
idinor	0:dcf3c92487ca	1	/**
idinor	0:dcf3c92487ca	2	* @file
idinor	0:dcf3c92487ca	3	* Address Resolution Protocol module for IP over Ethernet
idinor	0:dcf3c92487ca	4	*
idinor	0:dcf3c92487ca	5	* Functionally, ARP is divided into two parts. The first maps an IP address
idinor	0:dcf3c92487ca	6	* to a physical address when sending a packet, and the second part answers
idinor	0:dcf3c92487ca	7	* requests from other machines for our physical address.
idinor	0:dcf3c92487ca	8	*
idinor	0:dcf3c92487ca	9	* This implementation complies with RFC 826 (Ethernet ARP). It supports
idinor	0:dcf3c92487ca	10	* Gratuitious ARP from RFC3220 (IP Mobility Support for IPv4) section 4.6
idinor	0:dcf3c92487ca	11	* if an interface calls etharp_gratuitous(our_netif) upon address change.
idinor	0:dcf3c92487ca	12	*/
idinor	0:dcf3c92487ca	13
idinor	0:dcf3c92487ca	14	/*
idinor	0:dcf3c92487ca	15	* Copyright (c) 2001-2003 Swedish Institute of Computer Science.
idinor	0:dcf3c92487ca	16	* Copyright (c) 2003-2004 Leon Woestenberg <leon.woestenberg@axon.tv>
idinor	0:dcf3c92487ca	17	* Copyright (c) 2003-2004 Axon Digital Design B.V., The Netherlands.
idinor	0:dcf3c92487ca	18	* All rights reserved.
idinor	0:dcf3c92487ca	19	*
idinor	0:dcf3c92487ca	20	* Redistribution and use in source and binary forms, with or without modification,
idinor	0:dcf3c92487ca	21	* are permitted provided that the following conditions are met:
idinor	0:dcf3c92487ca	22	*
idinor	0:dcf3c92487ca	23	* 1. Redistributions of source code must retain the above copyright notice,
idinor	0:dcf3c92487ca	24	* this list of conditions and the following disclaimer.
idinor	0:dcf3c92487ca	25	* 2. Redistributions in binary form must reproduce the above copyright notice,
idinor	0:dcf3c92487ca	26	* this list of conditions and the following disclaimer in the documentation
idinor	0:dcf3c92487ca	27	* and/or other materials provided with the distribution.
idinor	0:dcf3c92487ca	28	* 3. The name of the author may not be used to endorse or promote products
idinor	0:dcf3c92487ca	29	* derived from this software without specific prior written permission.
idinor	0:dcf3c92487ca	30	*
idinor	0:dcf3c92487ca	31	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
idinor	0:dcf3c92487ca	32	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
idinor	0:dcf3c92487ca	33	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
idinor	0:dcf3c92487ca	34	* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
idinor	0:dcf3c92487ca	35	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
idinor	0:dcf3c92487ca	36	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
idinor	0:dcf3c92487ca	37	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
idinor	0:dcf3c92487ca	38	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
idinor	0:dcf3c92487ca	39	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
idinor	0:dcf3c92487ca	40	* OF SUCH DAMAGE.
idinor	0:dcf3c92487ca	41	*
idinor	0:dcf3c92487ca	42	* This file is part of the lwIP TCP/IP stack.
idinor	0:dcf3c92487ca	43	*
idinor	0:dcf3c92487ca	44	*/
idinor	0:dcf3c92487ca	45
idinor	0:dcf3c92487ca	46	#include "lwip/opt.h"
idinor	0:dcf3c92487ca	47
idinor	0:dcf3c92487ca	48	#if LWIP_ARP \|\| LWIP_ETHERNET
idinor	0:dcf3c92487ca	49
idinor	0:dcf3c92487ca	50	#include "lwip/ip_addr.h"
idinor	0:dcf3c92487ca	51	#include "lwip/def.h"
idinor	0:dcf3c92487ca	52	#include "lwip/ip.h"
idinor	0:dcf3c92487ca	53	#include "lwip/stats.h"
idinor	0:dcf3c92487ca	54	#include "lwip/snmp.h"
idinor	0:dcf3c92487ca	55	#include "lwip/dhcp.h"
idinor	0:dcf3c92487ca	56	#include "lwip/autoip.h"
idinor	0:dcf3c92487ca	57	#include "netif/etharp.h"
idinor	0:dcf3c92487ca	58
idinor	0:dcf3c92487ca	59	#if PPPOE_SUPPORT
idinor	0:dcf3c92487ca	60	#include "netif/ppp_oe.h"
idinor	0:dcf3c92487ca	61	#endif /* PPPOE_SUPPORT */
idinor	0:dcf3c92487ca	62
idinor	0:dcf3c92487ca	63	#include <string.h>
idinor	0:dcf3c92487ca	64
idinor	0:dcf3c92487ca	65	const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}};
idinor	0:dcf3c92487ca	66	const struct eth_addr ethzero = {{0,0,0,0,0,0}};
idinor	0:dcf3c92487ca	67
idinor	0:dcf3c92487ca	68	#if LWIP_ARP /* don't build if not configured for use in lwipopts.h */
idinor	0:dcf3c92487ca	69
idinor	0:dcf3c92487ca	70	/** the time an ARP entry stays valid after its last update,
idinor	0:dcf3c92487ca	71	* for ARP_TMR_INTERVAL = 5000, this is
idinor	0:dcf3c92487ca	72	* (240 * 5) seconds = 20 minutes.
idinor	0:dcf3c92487ca	73	*/
idinor	0:dcf3c92487ca	74	#define ARP_MAXAGE 240
idinor	0:dcf3c92487ca	75	/** the time an ARP entry stays pending after first request,
idinor	0:dcf3c92487ca	76	* for ARP_TMR_INTERVAL = 5000, this is
idinor	0:dcf3c92487ca	77	* (2 * 5) seconds = 10 seconds.
idinor	0:dcf3c92487ca	78	*
idinor	0:dcf3c92487ca	79	* @internal Keep this number at least 2, otherwise it might
idinor	0:dcf3c92487ca	80	* run out instantly if the timeout occurs directly after a request.
idinor	0:dcf3c92487ca	81	*/
idinor	0:dcf3c92487ca	82	#define ARP_MAXPENDING 2
idinor	0:dcf3c92487ca	83
idinor	0:dcf3c92487ca	84	#define HWTYPE_ETHERNET 1
idinor	0:dcf3c92487ca	85
idinor	0:dcf3c92487ca	86	enum etharp_state {
idinor	0:dcf3c92487ca	87	ETHARP_STATE_EMPTY = 0,
idinor	0:dcf3c92487ca	88	ETHARP_STATE_PENDING,
idinor	0:dcf3c92487ca	89	ETHARP_STATE_STABLE
idinor	0:dcf3c92487ca	90	};
idinor	0:dcf3c92487ca	91
idinor	0:dcf3c92487ca	92	struct etharp_entry {
idinor	0:dcf3c92487ca	93	#if ARP_QUEUEING
idinor	0:dcf3c92487ca	94	/** Pointer to queue of pending outgoing packets on this ARP entry. */
idinor	0:dcf3c92487ca	95	struct etharp_q_entry *q;
idinor	0:dcf3c92487ca	96	#endif /* ARP_QUEUEING */
idinor	0:dcf3c92487ca	97	ip_addr_t ipaddr;
idinor	0:dcf3c92487ca	98	struct eth_addr ethaddr;
idinor	0:dcf3c92487ca	99	#if LWIP_SNMP
idinor	0:dcf3c92487ca	100	struct netif *netif;
idinor	0:dcf3c92487ca	101	#endif /* LWIP_SNMP */
idinor	0:dcf3c92487ca	102	u8_t state;
idinor	0:dcf3c92487ca	103	u8_t ctime;
idinor	0:dcf3c92487ca	104	#if ETHARP_SUPPORT_STATIC_ENTRIES
idinor	0:dcf3c92487ca	105	u8_t static_entry;
idinor	0:dcf3c92487ca	106	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
idinor	0:dcf3c92487ca	107	};
idinor	0:dcf3c92487ca	108
idinor	0:dcf3c92487ca	109	static struct etharp_entry arp_table[ARP_TABLE_SIZE];
idinor	0:dcf3c92487ca	110
idinor	0:dcf3c92487ca	111	#if !LWIP_NETIF_HWADDRHINT
idinor	0:dcf3c92487ca	112	static u8_t etharp_cached_entry;
idinor	0:dcf3c92487ca	113	#endif /* !LWIP_NETIF_HWADDRHINT */
idinor	0:dcf3c92487ca	114
idinor	0:dcf3c92487ca	115	/** Try hard to create a new entry - we want the IP address to appear in
idinor	0:dcf3c92487ca	116	the cache (even if this means removing an active entry or so). */
idinor	0:dcf3c92487ca	117	#define ETHARP_FLAG_TRY_HARD 1
idinor	0:dcf3c92487ca	118	#define ETHARP_FLAG_FIND_ONLY 2
idinor	0:dcf3c92487ca	119	#define ETHARP_FLAG_STATIC_ENTRY 4
idinor	0:dcf3c92487ca	120
idinor	0:dcf3c92487ca	121	#if LWIP_NETIF_HWADDRHINT
idinor	0:dcf3c92487ca	122	#define ETHARP_SET_HINT(netif, hint) if (((netif) != NULL) && ((netif)->addr_hint != NULL)) \
idinor	0:dcf3c92487ca	123	*((netif)->addr_hint) = (hint);
idinor	0:dcf3c92487ca	124	#else /* LWIP_NETIF_HWADDRHINT */
idinor	0:dcf3c92487ca	125	#define ETHARP_SET_HINT(netif, hint) (etharp_cached_entry = (hint))
idinor	0:dcf3c92487ca	126	#endif /* LWIP_NETIF_HWADDRHINT */
idinor	0:dcf3c92487ca	127
idinor	0:dcf3c92487ca	128	static err_t update_arp_entry(struct netif netif, ip_addr_t ipaddr, struct eth_addr *ethaddr, u8_t flags);
idinor	0:dcf3c92487ca	129
idinor	0:dcf3c92487ca	130
idinor	0:dcf3c92487ca	131	/* Some checks, instead of etharp_init(): */
idinor	0:dcf3c92487ca	132	#if (LWIP_ARP && (ARP_TABLE_SIZE > 0x7f))
idinor	0:dcf3c92487ca	133	#error "ARP_TABLE_SIZE must fit in an s8_t, you have to reduce it in your lwipopts.h"
idinor	0:dcf3c92487ca	134	#endif
idinor	0:dcf3c92487ca	135
idinor	0:dcf3c92487ca	136
idinor	0:dcf3c92487ca	137	#if ARP_QUEUEING
idinor	0:dcf3c92487ca	138	/**
idinor	0:dcf3c92487ca	139	* Free a complete queue of etharp entries
idinor	0:dcf3c92487ca	140	*
idinor	0:dcf3c92487ca	141	* @param q a qeueue of etharp_q_entry's to free
idinor	0:dcf3c92487ca	142	*/
idinor	0:dcf3c92487ca	143	static void
idinor	0:dcf3c92487ca	144	free_etharp_q(struct etharp_q_entry *q)
idinor	0:dcf3c92487ca	145	{
idinor	0:dcf3c92487ca	146	struct etharp_q_entry *r;
idinor	0:dcf3c92487ca	147	LWIP_ASSERT("q != NULL", q != NULL);
idinor	0:dcf3c92487ca	148	LWIP_ASSERT("q->p != NULL", q->p != NULL);
idinor	0:dcf3c92487ca	149	while (q) {
idinor	0:dcf3c92487ca	150	r = q;
idinor	0:dcf3c92487ca	151	q = q->next;
idinor	0:dcf3c92487ca	152	LWIP_ASSERT("r->p != NULL", (r->p != NULL));
idinor	0:dcf3c92487ca	153	pbuf_free(r->p);
idinor	0:dcf3c92487ca	154	memp_free(MEMP_ARP_QUEUE, r);
idinor	0:dcf3c92487ca	155	}
idinor	0:dcf3c92487ca	156	}
idinor	0:dcf3c92487ca	157	#endif /* ARP_QUEUEING */
idinor	0:dcf3c92487ca	158
idinor	0:dcf3c92487ca	159	/** Clean up ARP table entries */
idinor	0:dcf3c92487ca	160	static void
idinor	0:dcf3c92487ca	161	free_entry(int i)
idinor	0:dcf3c92487ca	162	{
idinor	0:dcf3c92487ca	163	/* remove from SNMP ARP index tree */
idinor	0:dcf3c92487ca	164	snmp_delete_arpidx_tree(arp_table[i].netif, &arp_table[i].ipaddr);
idinor	0:dcf3c92487ca	165	#if ARP_QUEUEING
idinor	0:dcf3c92487ca	166	/* and empty packet queue */
idinor	0:dcf3c92487ca	167	if (arp_table[i].q != NULL) {
idinor	0:dcf3c92487ca	168	/* remove all queued packets */
idinor	0:dcf3c92487ca	169	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: freeing entry %"U16_F", packet queue %p.\n", (u16_t)i, (void *)(arp_table[i].q)));
idinor	0:dcf3c92487ca	170	free_etharp_q(arp_table[i].q);
idinor	0:dcf3c92487ca	171	arp_table[i].q = NULL;
idinor	0:dcf3c92487ca	172	}
idinor	0:dcf3c92487ca	173	#endif /* ARP_QUEUEING */
idinor	0:dcf3c92487ca	174	/* recycle entry for re-use */
idinor	0:dcf3c92487ca	175	arp_table[i].state = ETHARP_STATE_EMPTY;
idinor	0:dcf3c92487ca	176	#if ETHARP_SUPPORT_STATIC_ENTRIES
idinor	0:dcf3c92487ca	177	arp_table[i].static_entry = 0;
idinor	0:dcf3c92487ca	178	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
idinor	0:dcf3c92487ca	179	#ifdef LWIP_DEBUG
idinor	0:dcf3c92487ca	180	/* for debugging, clean out the complete entry */
idinor	0:dcf3c92487ca	181	arp_table[i].ctime = 0;
idinor	0:dcf3c92487ca	182	#if LWIP_SNMP
idinor	0:dcf3c92487ca	183	arp_table[i].netif = NULL;
idinor	0:dcf3c92487ca	184	#endif /* LWIP_SNMP */
idinor	0:dcf3c92487ca	185	ip_addr_set_zero(&arp_table[i].ipaddr);
idinor	0:dcf3c92487ca	186	arp_table[i].ethaddr = ethzero;
idinor	0:dcf3c92487ca	187	#endif /* LWIP_DEBUG */
idinor	0:dcf3c92487ca	188	}
idinor	0:dcf3c92487ca	189
idinor	0:dcf3c92487ca	190	/**
idinor	0:dcf3c92487ca	191	* Clears expired entries in the ARP table.
idinor	0:dcf3c92487ca	192	*
idinor	0:dcf3c92487ca	193	* This function should be called every ETHARP_TMR_INTERVAL milliseconds (5 seconds),
idinor	0:dcf3c92487ca	194	* in order to expire entries in the ARP table.
idinor	0:dcf3c92487ca	195	*/
idinor	0:dcf3c92487ca	196	void
idinor	0:dcf3c92487ca	197	etharp_tmr(void)
idinor	0:dcf3c92487ca	198	{
idinor	0:dcf3c92487ca	199	u8_t i;
idinor	0:dcf3c92487ca	200
idinor	0:dcf3c92487ca	201	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer\n"));
idinor	0:dcf3c92487ca	202	/* remove expired entries from the ARP table */
idinor	0:dcf3c92487ca	203	for (i = 0; i < ARP_TABLE_SIZE; ++i) {
idinor	0:dcf3c92487ca	204	u8_t state = arp_table[i].state;
idinor	0:dcf3c92487ca	205	if (state != ETHARP_STATE_EMPTY
idinor	0:dcf3c92487ca	206	#if ETHARP_SUPPORT_STATIC_ENTRIES
idinor	0:dcf3c92487ca	207	&& (arp_table[i].static_entry == 0)
idinor	0:dcf3c92487ca	208	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
idinor	0:dcf3c92487ca	209	) {
idinor	0:dcf3c92487ca	210	arp_table[i].ctime++;
idinor	0:dcf3c92487ca	211	if ((arp_table[i].ctime >= ARP_MAXAGE) \|\|
idinor	0:dcf3c92487ca	212	((arp_table[i].state == ETHARP_STATE_PENDING) &&
idinor	0:dcf3c92487ca	213	(arp_table[i].ctime >= ARP_MAXPENDING))) {
idinor	0:dcf3c92487ca	214	/* pending or stable entry has become old! */
idinor	0:dcf3c92487ca	215	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: expired %s entry %"U16_F".\n",
idinor	0:dcf3c92487ca	216	arp_table[i].state == ETHARP_STATE_STABLE ? "stable" : "pending", (u16_t)i));
idinor	0:dcf3c92487ca	217	/* clean up entries that have just been expired */
idinor	0:dcf3c92487ca	218	free_entry(i);
idinor	0:dcf3c92487ca	219	}
idinor	0:dcf3c92487ca	220	#if ARP_QUEUEING
idinor	0:dcf3c92487ca	221	/* still pending entry? (not expired) */
idinor	0:dcf3c92487ca	222	if (arp_table[i].state == ETHARP_STATE_PENDING) {
idinor	0:dcf3c92487ca	223	/* resend an ARP query here? */
idinor	0:dcf3c92487ca	224	}
idinor	0:dcf3c92487ca	225	#endif /* ARP_QUEUEING */
idinor	0:dcf3c92487ca	226	}
idinor	0:dcf3c92487ca	227	}
idinor	0:dcf3c92487ca	228	}
idinor	0:dcf3c92487ca	229
idinor	0:dcf3c92487ca	230	/**
idinor	0:dcf3c92487ca	231	* Search the ARP table for a matching or new entry.
idinor	0:dcf3c92487ca	232	*
idinor	0:dcf3c92487ca	233	* If an IP address is given, return a pending or stable ARP entry that matches
idinor	0:dcf3c92487ca	234	* the address. If no match is found, create a new entry with this address set,
idinor	0:dcf3c92487ca	235	* but in state ETHARP_EMPTY. The caller must check and possibly change the
idinor	0:dcf3c92487ca	236	* state of the returned entry.
idinor	0:dcf3c92487ca	237	*
idinor	0:dcf3c92487ca	238	* If ipaddr is NULL, return a initialized new entry in state ETHARP_EMPTY.
idinor	0:dcf3c92487ca	239	*
idinor	0:dcf3c92487ca	240	* In all cases, attempt to create new entries from an empty entry. If no
idinor	0:dcf3c92487ca	241	* empty entries are available and ETHARP_FLAG_TRY_HARD flag is set, recycle
idinor	0:dcf3c92487ca	242	* old entries. Heuristic choose the least important entry for recycling.
idinor	0:dcf3c92487ca	243	*
idinor	0:dcf3c92487ca	244	* @param ipaddr IP address to find in ARP cache, or to add if not found.
idinor	0:dcf3c92487ca	245	* @param flags @see definition of ETHARP_FLAG_*
idinor	0:dcf3c92487ca	246	* @param netif netif related to this address (used for NETIF_HWADDRHINT)
idinor	0:dcf3c92487ca	247	*
idinor	0:dcf3c92487ca	248	* @return The ARP entry index that matched or is created, ERR_MEM if no
idinor	0:dcf3c92487ca	249	* entry is found or could be recycled.
idinor	0:dcf3c92487ca	250	*/
idinor	0:dcf3c92487ca	251	static s8_t
idinor	0:dcf3c92487ca	252	find_entry(ip_addr_t *ipaddr, u8_t flags)
idinor	0:dcf3c92487ca	253	{
idinor	0:dcf3c92487ca	254	s8_t old_pending = ARP_TABLE_SIZE, old_stable = ARP_TABLE_SIZE;
idinor	0:dcf3c92487ca	255	s8_t empty = ARP_TABLE_SIZE;
idinor	0:dcf3c92487ca	256	u8_t i = 0, age_pending = 0, age_stable = 0;
idinor	0:dcf3c92487ca	257	#if ARP_QUEUEING
idinor	0:dcf3c92487ca	258	/* oldest entry with packets on queue */
idinor	0:dcf3c92487ca	259	s8_t old_queue = ARP_TABLE_SIZE;
idinor	0:dcf3c92487ca	260	/* its age */
idinor	0:dcf3c92487ca	261	u8_t age_queue = 0;
idinor	0:dcf3c92487ca	262	#endif /* ARP_QUEUEING */
idinor	0:dcf3c92487ca	263
idinor	0:dcf3c92487ca	264	/**
idinor	0:dcf3c92487ca	265	* a) do a search through the cache, remember candidates
idinor	0:dcf3c92487ca	266	* b) select candidate entry
idinor	0:dcf3c92487ca	267	* c) create new entry
idinor	0:dcf3c92487ca	268	*/
idinor	0:dcf3c92487ca	269
idinor	0:dcf3c92487ca	270	/* a) in a single search sweep, do all of this
idinor	0:dcf3c92487ca	271	* 1) remember the first empty entry (if any)
idinor	0:dcf3c92487ca	272	* 2) remember the oldest stable entry (if any)
idinor	0:dcf3c92487ca	273	* 3) remember the oldest pending entry without queued packets (if any)
idinor	0:dcf3c92487ca	274	* 4) remember the oldest pending entry with queued packets (if any)
idinor	0:dcf3c92487ca	275	* 5) search for a matching IP entry, either pending or stable
idinor	0:dcf3c92487ca	276	* until 5 matches, or all entries are searched for.
idinor	0:dcf3c92487ca	277	*/
idinor	0:dcf3c92487ca	278
idinor	0:dcf3c92487ca	279	for (i = 0; i < ARP_TABLE_SIZE; ++i) {
idinor	0:dcf3c92487ca	280	u8_t state = arp_table[i].state;
idinor	0:dcf3c92487ca	281	/* no empty entry found yet and now we do find one? */
idinor	0:dcf3c92487ca	282	if ((empty == ARP_TABLE_SIZE) && (state == ETHARP_STATE_EMPTY)) {
idinor	0:dcf3c92487ca	283	LWIP_DEBUGF(ETHARP_DEBUG, ("find_entry: found empty entry %"U16_F"\n", (u16_t)i));
idinor	0:dcf3c92487ca	284	/* remember first empty entry */
idinor	0:dcf3c92487ca	285	empty = i;
idinor	0:dcf3c92487ca	286	} else if (state != ETHARP_STATE_EMPTY) {
idinor	0:dcf3c92487ca	287	LWIP_ASSERT("state == ETHARP_STATE_PENDING \|\| state == ETHARP_STATE_STABLE",
idinor	0:dcf3c92487ca	288	state == ETHARP_STATE_PENDING \|\| state == ETHARP_STATE_STABLE);
idinor	0:dcf3c92487ca	289	/* if given, does IP address match IP address in ARP entry? */
idinor	0:dcf3c92487ca	290	if (ipaddr && ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
idinor	0:dcf3c92487ca	291	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: found matching entry %"U16_F"\n", (u16_t)i));
idinor	0:dcf3c92487ca	292	/* found exact IP address match, simply bail out */
idinor	0:dcf3c92487ca	293	return i;
idinor	0:dcf3c92487ca	294	}
idinor	0:dcf3c92487ca	295	/* pending entry? */
idinor	0:dcf3c92487ca	296	if (state == ETHARP_STATE_PENDING) {
idinor	0:dcf3c92487ca	297	/* pending with queued packets? */
idinor	0:dcf3c92487ca	298	#if ARP_QUEUEING
idinor	0:dcf3c92487ca	299	if (arp_table[i].q != NULL) {
idinor	0:dcf3c92487ca	300	if (arp_table[i].ctime >= age_queue) {
idinor	0:dcf3c92487ca	301	old_queue = i;
idinor	0:dcf3c92487ca	302	age_queue = arp_table[i].ctime;
idinor	0:dcf3c92487ca	303	}
idinor	0:dcf3c92487ca	304	} else
idinor	0:dcf3c92487ca	305	#endif /* ARP_QUEUEING */
idinor	0:dcf3c92487ca	306	/* pending without queued packets? */
idinor	0:dcf3c92487ca	307	{
idinor	0:dcf3c92487ca	308	if (arp_table[i].ctime >= age_pending) {
idinor	0:dcf3c92487ca	309	old_pending = i;
idinor	0:dcf3c92487ca	310	age_pending = arp_table[i].ctime;
idinor	0:dcf3c92487ca	311	}
idinor	0:dcf3c92487ca	312	}
idinor	0:dcf3c92487ca	313	/* stable entry? */
idinor	0:dcf3c92487ca	314	} else if (state == ETHARP_STATE_STABLE) {
idinor	0:dcf3c92487ca	315	#if ETHARP_SUPPORT_STATIC_ENTRIES
idinor	0:dcf3c92487ca	316	/* don't record old_stable for static entries since they never expire */
idinor	0:dcf3c92487ca	317	if (arp_table[i].static_entry == 0)
idinor	0:dcf3c92487ca	318	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
idinor	0:dcf3c92487ca	319	{
idinor	0:dcf3c92487ca	320	/* remember entry with oldest stable entry in oldest, its age in maxtime */
idinor	0:dcf3c92487ca	321	if (arp_table[i].ctime >= age_stable) {
idinor	0:dcf3c92487ca	322	old_stable = i;
idinor	0:dcf3c92487ca	323	age_stable = arp_table[i].ctime;
idinor	0:dcf3c92487ca	324	}
idinor	0:dcf3c92487ca	325	}
idinor	0:dcf3c92487ca	326	}
idinor	0:dcf3c92487ca	327	}
idinor	0:dcf3c92487ca	328	}
idinor	0:dcf3c92487ca	329	/* { we have no match } => try to create a new entry */
idinor	0:dcf3c92487ca	330
idinor	0:dcf3c92487ca	331	/* don't create new entry, only search? */
idinor	0:dcf3c92487ca	332	if (((flags & ETHARP_FLAG_FIND_ONLY) != 0) \|\|
idinor	0:dcf3c92487ca	333	/* or no empty entry found and not allowed to recycle? */
idinor	0:dcf3c92487ca	334	((empty == ARP_TABLE_SIZE) && ((flags & ETHARP_FLAG_TRY_HARD) == 0))) {
idinor	0:dcf3c92487ca	335	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: no empty entry found and not allowed to recycle\n"));
idinor	0:dcf3c92487ca	336	return (s8_t)ERR_MEM;
idinor	0:dcf3c92487ca	337	}
idinor	0:dcf3c92487ca	338
idinor	0:dcf3c92487ca	339	/* b) choose the least destructive entry to recycle:
idinor	0:dcf3c92487ca	340	* 1) empty entry
idinor	0:dcf3c92487ca	341	* 2) oldest stable entry
idinor	0:dcf3c92487ca	342	* 3) oldest pending entry without queued packets
idinor	0:dcf3c92487ca	343	* 4) oldest pending entry with queued packets
idinor	0:dcf3c92487ca	344	*
idinor	0:dcf3c92487ca	345	* { ETHARP_FLAG_TRY_HARD is set at this point }
idinor	0:dcf3c92487ca	346	*/
idinor	0:dcf3c92487ca	347
idinor	0:dcf3c92487ca	348	/* 1) empty entry available? */
idinor	0:dcf3c92487ca	349	if (empty < ARP_TABLE_SIZE) {
idinor	0:dcf3c92487ca	350	i = empty;
idinor	0:dcf3c92487ca	351	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting empty entry %"U16_F"\n", (u16_t)i));
idinor	0:dcf3c92487ca	352	} else {
idinor	0:dcf3c92487ca	353	/* 2) found recyclable stable entry? */
idinor	0:dcf3c92487ca	354	if (old_stable < ARP_TABLE_SIZE) {
idinor	0:dcf3c92487ca	355	/* recycle oldest stable*/
idinor	0:dcf3c92487ca	356	i = old_stable;
idinor	0:dcf3c92487ca	357	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest stable entry %"U16_F"\n", (u16_t)i));
idinor	0:dcf3c92487ca	358	#if ARP_QUEUEING
idinor	0:dcf3c92487ca	359	/* no queued packets should exist on stable entries */
idinor	0:dcf3c92487ca	360	LWIP_ASSERT("arp_table[i].q == NULL", arp_table[i].q == NULL);
idinor	0:dcf3c92487ca	361	#endif /* ARP_QUEUEING */
idinor	0:dcf3c92487ca	362	/* 3) found recyclable pending entry without queued packets? */
idinor	0:dcf3c92487ca	363	} else if (old_pending < ARP_TABLE_SIZE) {
idinor	0:dcf3c92487ca	364	/* recycle oldest pending */
idinor	0:dcf3c92487ca	365	i = old_pending;
idinor	0:dcf3c92487ca	366	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest pending entry %"U16_F" (without queue)\n", (u16_t)i));
idinor	0:dcf3c92487ca	367	#if ARP_QUEUEING
idinor	0:dcf3c92487ca	368	/* 4) found recyclable pending entry with queued packets? */
idinor	0:dcf3c92487ca	369	} else if (old_queue < ARP_TABLE_SIZE) {
idinor	0:dcf3c92487ca	370	/* recycle oldest pending (queued packets are free in free_entry) */
idinor	0:dcf3c92487ca	371	i = old_queue;
idinor	0:dcf3c92487ca	372	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest pending entry %"U16_F", freeing packet queue %p\n", (u16_t)i, (void *)(arp_table[i].q)));
idinor	0:dcf3c92487ca	373	#endif /* ARP_QUEUEING */
idinor	0:dcf3c92487ca	374	/* no empty or recyclable entries found */
idinor	0:dcf3c92487ca	375	} else {
idinor	0:dcf3c92487ca	376	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: no empty or recyclable entries found\n"));
idinor	0:dcf3c92487ca	377	return (s8_t)ERR_MEM;
idinor	0:dcf3c92487ca	378	}
idinor	0:dcf3c92487ca	379
idinor	0:dcf3c92487ca	380	/* { empty or recyclable entry found } */
idinor	0:dcf3c92487ca	381	LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
idinor	0:dcf3c92487ca	382	free_entry(i);
idinor	0:dcf3c92487ca	383	}
idinor	0:dcf3c92487ca	384
idinor	0:dcf3c92487ca	385	LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
idinor	0:dcf3c92487ca	386	LWIP_ASSERT("arp_table[i].state == ETHARP_STATE_EMPTY",
idinor	0:dcf3c92487ca	387	arp_table[i].state == ETHARP_STATE_EMPTY);
idinor	0:dcf3c92487ca	388
idinor	0:dcf3c92487ca	389	/* IP address given? */
idinor	0:dcf3c92487ca	390	if (ipaddr != NULL) {
idinor	0:dcf3c92487ca	391	/* set IP address */
idinor	0:dcf3c92487ca	392	ip_addr_copy(arp_table[i].ipaddr, *ipaddr);
idinor	0:dcf3c92487ca	393	}
idinor	0:dcf3c92487ca	394	arp_table[i].ctime = 0;
idinor	0:dcf3c92487ca	395	#if ETHARP_SUPPORT_STATIC_ENTRIES
idinor	0:dcf3c92487ca	396	arp_table[i].static_entry = 0;
idinor	0:dcf3c92487ca	397	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
idinor	0:dcf3c92487ca	398	return (err_t)i;
idinor	0:dcf3c92487ca	399	}
idinor	0:dcf3c92487ca	400
idinor	0:dcf3c92487ca	401	/**
idinor	0:dcf3c92487ca	402	* Send an IP packet on the network using netif->linkoutput
idinor	0:dcf3c92487ca	403	* The ethernet header is filled in before sending.
idinor	0:dcf3c92487ca	404	*
idinor	0:dcf3c92487ca	405	* @params netif the lwIP network interface on which to send the packet
idinor	0:dcf3c92487ca	406	* @params p the packet to send, p->payload pointing to the (uninitialized) ethernet header
idinor	0:dcf3c92487ca	407	* @params src the source MAC address to be copied into the ethernet header
idinor	0:dcf3c92487ca	408	* @params dst the destination MAC address to be copied into the ethernet header
idinor	0:dcf3c92487ca	409	* @return ERR_OK if the packet was sent, any other err_t on failure
idinor	0:dcf3c92487ca	410	*/
idinor	0:dcf3c92487ca	411	static err_t
idinor	0:dcf3c92487ca	412	etharp_send_ip(struct netif netif, struct pbuf p, struct eth_addr src, struct eth_addr dst)
idinor	0:dcf3c92487ca	413	{
idinor	0:dcf3c92487ca	414	struct eth_hdr ethhdr = (struct eth_hdr )p->payload;
idinor	0:dcf3c92487ca	415
idinor	0:dcf3c92487ca	416	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
idinor	0:dcf3c92487ca	417	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
idinor	0:dcf3c92487ca	418	ETHADDR32_COPY(&ethhdr->dest, dst);
idinor	0:dcf3c92487ca	419	ETHADDR16_COPY(&ethhdr->src, src);
idinor	0:dcf3c92487ca	420	ethhdr->type = PP_HTONS(ETHTYPE_IP);
idinor	0:dcf3c92487ca	421	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_send_ip: sending packet %p\n", (void *)p));
idinor	0:dcf3c92487ca	422	/* send the packet */
idinor	0:dcf3c92487ca	423	return netif->linkoutput(netif, p);
idinor	0:dcf3c92487ca	424	}
idinor	0:dcf3c92487ca	425
idinor	0:dcf3c92487ca	426	/**
idinor	0:dcf3c92487ca	427	* Update (or insert) a IP/MAC address pair in the ARP cache.
idinor	0:dcf3c92487ca	428	*
idinor	0:dcf3c92487ca	429	* If a pending entry is resolved, any queued packets will be sent
idinor	0:dcf3c92487ca	430	* at this point.
idinor	0:dcf3c92487ca	431	*
idinor	0:dcf3c92487ca	432	* @param netif netif related to this entry (used for NETIF_ADDRHINT)
idinor	0:dcf3c92487ca	433	* @param ipaddr IP address of the inserted ARP entry.
idinor	0:dcf3c92487ca	434	* @param ethaddr Ethernet address of the inserted ARP entry.
idinor	0:dcf3c92487ca	435	* @param flags @see definition of ETHARP_FLAG_*
idinor	0:dcf3c92487ca	436	*
idinor	0:dcf3c92487ca	437	* @return
idinor	0:dcf3c92487ca	438	* - ERR_OK Succesfully updated ARP cache.
idinor	0:dcf3c92487ca	439	* - ERR_MEM If we could not add a new ARP entry when ETHARP_FLAG_TRY_HARD was set.
idinor	0:dcf3c92487ca	440	* - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
idinor	0:dcf3c92487ca	441	*
idinor	0:dcf3c92487ca	442	* @see pbuf_free()
idinor	0:dcf3c92487ca	443	*/
idinor	0:dcf3c92487ca	444	static err_t
idinor	0:dcf3c92487ca	445	update_arp_entry(struct netif netif, ip_addr_t ipaddr, struct eth_addr *ethaddr, u8_t flags)
idinor	0:dcf3c92487ca	446	{
idinor	0:dcf3c92487ca	447	s8_t i;
idinor	0:dcf3c92487ca	448	LWIP_ASSERT("netif->hwaddr_len == ETHARP_HWADDR_LEN", netif->hwaddr_len == ETHARP_HWADDR_LEN);
idinor	0:dcf3c92487ca	449	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: %"U16_F".%"U16_F".%"U16_F".%"U16_F" - %02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F"\n",
idinor	0:dcf3c92487ca	450	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
idinor	0:dcf3c92487ca	451	ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
idinor	0:dcf3c92487ca	452	ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
idinor	0:dcf3c92487ca	453	/* non-unicast address? */
idinor	0:dcf3c92487ca	454	if (ip_addr_isany(ipaddr) \|\|
idinor	0:dcf3c92487ca	455	ip_addr_isbroadcast(ipaddr, netif) \|\|
idinor	0:dcf3c92487ca	456	ip_addr_ismulticast(ipaddr)) {
idinor	0:dcf3c92487ca	457	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: will not add non-unicast IP address to ARP cache\n"));
idinor	0:dcf3c92487ca	458	return ERR_ARG;
idinor	0:dcf3c92487ca	459	}
idinor	0:dcf3c92487ca	460	/* find or create ARP entry */
idinor	0:dcf3c92487ca	461	i = find_entry(ipaddr, flags);
idinor	0:dcf3c92487ca	462	/* bail out if no entry could be found */
idinor	0:dcf3c92487ca	463	if (i < 0) {
idinor	0:dcf3c92487ca	464	return (err_t)i;
idinor	0:dcf3c92487ca	465	}
idinor	0:dcf3c92487ca	466
idinor	0:dcf3c92487ca	467	#if ETHARP_SUPPORT_STATIC_ENTRIES
idinor	0:dcf3c92487ca	468	if (flags & ETHARP_FLAG_STATIC_ENTRY) {
idinor	0:dcf3c92487ca	469	/* record static type */
idinor	0:dcf3c92487ca	470	arp_table[i].static_entry = 1;
idinor	0:dcf3c92487ca	471	}
idinor	0:dcf3c92487ca	472	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
idinor	0:dcf3c92487ca	473
idinor	0:dcf3c92487ca	474	/* mark it stable */
idinor	0:dcf3c92487ca	475	arp_table[i].state = ETHARP_STATE_STABLE;
idinor	0:dcf3c92487ca	476
idinor	0:dcf3c92487ca	477	#if LWIP_SNMP
idinor	0:dcf3c92487ca	478	/* record network interface */
idinor	0:dcf3c92487ca	479	arp_table[i].netif = netif;
idinor	0:dcf3c92487ca	480	#endif /* LWIP_SNMP */
idinor	0:dcf3c92487ca	481	/* insert in SNMP ARP index tree */
idinor	0:dcf3c92487ca	482	snmp_insert_arpidx_tree(netif, &arp_table[i].ipaddr);
idinor	0:dcf3c92487ca	483
idinor	0:dcf3c92487ca	484	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: updating stable entry %"S16_F"\n", (s16_t)i));
idinor	0:dcf3c92487ca	485	/* update address */
idinor	0:dcf3c92487ca	486	ETHADDR32_COPY(&arp_table[i].ethaddr, ethaddr);
idinor	0:dcf3c92487ca	487	/* reset time stamp */
idinor	0:dcf3c92487ca	488	arp_table[i].ctime = 0;
idinor	0:dcf3c92487ca	489	#if ARP_QUEUEING
idinor	0:dcf3c92487ca	490	/* this is where we will send out queued packets! */
idinor	0:dcf3c92487ca	491	while (arp_table[i].q != NULL) {
idinor	0:dcf3c92487ca	492	struct pbuf *p;
idinor	0:dcf3c92487ca	493	/* remember remainder of queue */
idinor	0:dcf3c92487ca	494	struct etharp_q_entry *q = arp_table[i].q;
idinor	0:dcf3c92487ca	495	/* pop first item off the queue */
idinor	0:dcf3c92487ca	496	arp_table[i].q = q->next;
idinor	0:dcf3c92487ca	497	/* get the packet pointer */
idinor	0:dcf3c92487ca	498	p = q->p;
idinor	0:dcf3c92487ca	499	/* now queue entry can be freed */
idinor	0:dcf3c92487ca	500	memp_free(MEMP_ARP_QUEUE, q);
idinor	0:dcf3c92487ca	501	/* send the queued IP packet */
idinor	0:dcf3c92487ca	502	etharp_send_ip(netif, p, (struct eth_addr*)(netif->hwaddr), ethaddr);
idinor	0:dcf3c92487ca	503	/* free the queued IP packet */
idinor	0:dcf3c92487ca	504	pbuf_free(p);
idinor	0:dcf3c92487ca	505	}
idinor	0:dcf3c92487ca	506	#endif /* ARP_QUEUEING */
idinor	0:dcf3c92487ca	507	return ERR_OK;
idinor	0:dcf3c92487ca	508	}
idinor	0:dcf3c92487ca	509
idinor	0:dcf3c92487ca	510	#if ETHARP_SUPPORT_STATIC_ENTRIES
idinor	0:dcf3c92487ca	511	/** Add a new static entry to the ARP table. If an entry exists for the
idinor	0:dcf3c92487ca	512	* specified IP address, this entry is overwritten.
idinor	0:dcf3c92487ca	513	* If packets are queued for the specified IP address, they are sent out.
idinor	0:dcf3c92487ca	514	*
idinor	0:dcf3c92487ca	515	* @param ipaddr IP address for the new static entry
idinor	0:dcf3c92487ca	516	* @param ethaddr ethernet address for the new static entry
idinor	0:dcf3c92487ca	517	* @return @see return values of etharp_add_static_entry
idinor	0:dcf3c92487ca	518	*/
idinor	0:dcf3c92487ca	519	err_t
idinor	0:dcf3c92487ca	520	etharp_add_static_entry(ip_addr_t ipaddr, struct eth_addr ethaddr)
idinor	0:dcf3c92487ca	521	{
idinor	0:dcf3c92487ca	522	struct netif *netif;
idinor	0:dcf3c92487ca	523	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_add_static_entry: %"U16_F".%"U16_F".%"U16_F".%"U16_F" - %02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F":%02"X16_F"\n",
idinor	0:dcf3c92487ca	524	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
idinor	0:dcf3c92487ca	525	ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
idinor	0:dcf3c92487ca	526	ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
idinor	0:dcf3c92487ca	527
idinor	0:dcf3c92487ca	528	netif = ip_route(ipaddr);
idinor	0:dcf3c92487ca	529	if (netif == NULL) {
idinor	0:dcf3c92487ca	530	return ERR_RTE;
idinor	0:dcf3c92487ca	531	}
idinor	0:dcf3c92487ca	532
idinor	0:dcf3c92487ca	533	return update_arp_entry(netif, ipaddr, ethaddr, ETHARP_FLAG_TRY_HARD \| ETHARP_FLAG_STATIC_ENTRY);
idinor	0:dcf3c92487ca	534	}
idinor	0:dcf3c92487ca	535
idinor	0:dcf3c92487ca	536	/** Remove a static entry from the ARP table previously added with a call to
idinor	0:dcf3c92487ca	537	* etharp_add_static_entry.
idinor	0:dcf3c92487ca	538	*
idinor	0:dcf3c92487ca	539	* @param ipaddr IP address of the static entry to remove
idinor	0:dcf3c92487ca	540	* @return ERR_OK: entry removed
idinor	0:dcf3c92487ca	541	* ERR_MEM: entry wasn't found
idinor	0:dcf3c92487ca	542	* ERR_ARG: entry wasn't a static entry but a dynamic one
idinor	0:dcf3c92487ca	543	*/
idinor	0:dcf3c92487ca	544	err_t
idinor	0:dcf3c92487ca	545	etharp_remove_static_entry(ip_addr_t *ipaddr)
idinor	0:dcf3c92487ca	546	{
idinor	0:dcf3c92487ca	547	s8_t i;
idinor	0:dcf3c92487ca	548	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_remove_static_entry: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
idinor	0:dcf3c92487ca	549	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr)));
idinor	0:dcf3c92487ca	550
idinor	0:dcf3c92487ca	551	/* find or create ARP entry */
idinor	0:dcf3c92487ca	552	i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
idinor	0:dcf3c92487ca	553	/* bail out if no entry could be found */
idinor	0:dcf3c92487ca	554	if (i < 0) {
idinor	0:dcf3c92487ca	555	return (err_t)i;
idinor	0:dcf3c92487ca	556	}
idinor	0:dcf3c92487ca	557
idinor	0:dcf3c92487ca	558	if ((arp_table[i].state != ETHARP_STATE_STABLE) \|\|
idinor	0:dcf3c92487ca	559	(arp_table[i].static_entry == 0)) {
idinor	0:dcf3c92487ca	560	/* entry wasn't a static entry, cannot remove it */
idinor	0:dcf3c92487ca	561	return ERR_ARG;
idinor	0:dcf3c92487ca	562	}
idinor	0:dcf3c92487ca	563	/* entry found, free it */
idinor	0:dcf3c92487ca	564	free_entry(i);
idinor	0:dcf3c92487ca	565	return ERR_OK;
idinor	0:dcf3c92487ca	566	}
idinor	0:dcf3c92487ca	567	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
idinor	0:dcf3c92487ca	568
idinor	0:dcf3c92487ca	569	/**
idinor	0:dcf3c92487ca	570	* Finds (stable) ethernet/IP address pair from ARP table
idinor	0:dcf3c92487ca	571	* using interface and IP address index.
idinor	0:dcf3c92487ca	572	* @note the addresses in the ARP table are in network order!
idinor	0:dcf3c92487ca	573	*
idinor	0:dcf3c92487ca	574	* @param netif points to interface index
idinor	0:dcf3c92487ca	575	* @param ipaddr points to the (network order) IP address index
idinor	0:dcf3c92487ca	576	* @param eth_ret points to return pointer
idinor	0:dcf3c92487ca	577	* @param ip_ret points to return pointer
idinor	0:dcf3c92487ca	578	* @return table index if found, -1 otherwise
idinor	0:dcf3c92487ca	579	*/
idinor	0:dcf3c92487ca	580	s8_t
idinor	0:dcf3c92487ca	581	etharp_find_addr(struct netif netif, ip_addr_t ipaddr,
idinor	0:dcf3c92487ca	582	struct eth_addr eth_ret, ip_addr_t ip_ret)
idinor	0:dcf3c92487ca	583	{
idinor	0:dcf3c92487ca	584	s8_t i;
idinor	0:dcf3c92487ca	585
idinor	0:dcf3c92487ca	586	LWIP_ASSERT("eth_ret != NULL && ip_ret != NULL",
idinor	0:dcf3c92487ca	587	eth_ret != NULL && ip_ret != NULL);
idinor	0:dcf3c92487ca	588
idinor	0:dcf3c92487ca	589	LWIP_UNUSED_ARG(netif);
idinor	0:dcf3c92487ca	590
idinor	0:dcf3c92487ca	591	i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
idinor	0:dcf3c92487ca	592	if((i >= 0) && arp_table[i].state == ETHARP_STATE_STABLE) {
idinor	0:dcf3c92487ca	593	*eth_ret = &arp_table[i].ethaddr;
idinor	0:dcf3c92487ca	594	*ip_ret = &arp_table[i].ipaddr;
idinor	0:dcf3c92487ca	595	return i;
idinor	0:dcf3c92487ca	596	}
idinor	0:dcf3c92487ca	597	return -1;
idinor	0:dcf3c92487ca	598	}
idinor	0:dcf3c92487ca	599
idinor	0:dcf3c92487ca	600	#if ETHARP_TRUST_IP_MAC
idinor	0:dcf3c92487ca	601	/**
idinor	0:dcf3c92487ca	602	* Updates the ARP table using the given IP packet.
idinor	0:dcf3c92487ca	603	*
idinor	0:dcf3c92487ca	604	* Uses the incoming IP packet's source address to update the
idinor	0:dcf3c92487ca	605	* ARP cache for the local network. The function does not alter
idinor	0:dcf3c92487ca	606	* or free the packet. This function must be called before the
idinor	0:dcf3c92487ca	607	* packet p is passed to the IP layer.
idinor	0:dcf3c92487ca	608	*
idinor	0:dcf3c92487ca	609	* @param netif The lwIP network interface on which the IP packet pbuf arrived.
idinor	0:dcf3c92487ca	610	* @param p The IP packet that arrived on netif.
idinor	0:dcf3c92487ca	611	*
idinor	0:dcf3c92487ca	612	* @return NULL
idinor	0:dcf3c92487ca	613	*
idinor	0:dcf3c92487ca	614	* @see pbuf_free()
idinor	0:dcf3c92487ca	615	*/
idinor	0:dcf3c92487ca	616	static void
idinor	0:dcf3c92487ca	617	etharp_ip_input(struct netif netif, struct pbuf p)
idinor	0:dcf3c92487ca	618	{
idinor	0:dcf3c92487ca	619	struct eth_hdr *ethhdr;
idinor	0:dcf3c92487ca	620	struct ip_hdr *iphdr;
idinor	0:dcf3c92487ca	621	ip_addr_t iphdr_src;
idinor	0:dcf3c92487ca	622	LWIP_ERROR("netif != NULL", (netif != NULL), return;);
idinor	0:dcf3c92487ca	623
idinor	0:dcf3c92487ca	624	/* Only insert an entry if the source IP address of the
idinor	0:dcf3c92487ca	625	incoming IP packet comes from a host on the local network. */
idinor	0:dcf3c92487ca	626	ethhdr = (struct eth_hdr *)p->payload;
idinor	0:dcf3c92487ca	627	iphdr = (struct ip_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
idinor	0:dcf3c92487ca	628	#if ETHARP_SUPPORT_VLAN
idinor	0:dcf3c92487ca	629	if (ethhdr->type == ETHTYPE_VLAN) {
idinor	0:dcf3c92487ca	630	iphdr = (struct ip_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
idinor	0:dcf3c92487ca	631	}
idinor	0:dcf3c92487ca	632	#endif /* ETHARP_SUPPORT_VLAN */
idinor	0:dcf3c92487ca	633
idinor	0:dcf3c92487ca	634	ip_addr_copy(iphdr_src, iphdr->src);
idinor	0:dcf3c92487ca	635
idinor	0:dcf3c92487ca	636	/* source is not on the local network? */
idinor	0:dcf3c92487ca	637	if (!ip_addr_netcmp(&iphdr_src, &(netif->ip_addr), &(netif->netmask))) {
idinor	0:dcf3c92487ca	638	/* do nothing */
idinor	0:dcf3c92487ca	639	return;
idinor	0:dcf3c92487ca	640	}
idinor	0:dcf3c92487ca	641
idinor	0:dcf3c92487ca	642	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_ip_input: updating ETHARP table.\n"));
idinor	0:dcf3c92487ca	643	/* update the source IP address in the cache, if present */
idinor	0:dcf3c92487ca	644	/* @todo We could use ETHARP_FLAG_TRY_HARD if we think we are going to talk
idinor	0:dcf3c92487ca	645	* back soon (for example, if the destination IP address is ours. */
idinor	0:dcf3c92487ca	646	update_arp_entry(netif, &iphdr_src, &(ethhdr->src), ETHARP_FLAG_FIND_ONLY);
idinor	0:dcf3c92487ca	647	}
idinor	0:dcf3c92487ca	648	#endif /* ETHARP_TRUST_IP_MAC */
idinor	0:dcf3c92487ca	649
idinor	0:dcf3c92487ca	650	/**
idinor	0:dcf3c92487ca	651	* Responds to ARP requests to us. Upon ARP replies to us, add entry to cache
idinor	0:dcf3c92487ca	652	* send out queued IP packets. Updates cache with snooped address pairs.
idinor	0:dcf3c92487ca	653	*
idinor	0:dcf3c92487ca	654	* Should be called for incoming ARP packets. The pbuf in the argument
idinor	0:dcf3c92487ca	655	* is freed by this function.
idinor	0:dcf3c92487ca	656	*
idinor	0:dcf3c92487ca	657	* @param netif The lwIP network interface on which the ARP packet pbuf arrived.
idinor	0:dcf3c92487ca	658	* @param ethaddr Ethernet address of netif.
idinor	0:dcf3c92487ca	659	* @param p The ARP packet that arrived on netif. Is freed by this function.
idinor	0:dcf3c92487ca	660	*
idinor	0:dcf3c92487ca	661	* @return NULL
idinor	0:dcf3c92487ca	662	*
idinor	0:dcf3c92487ca	663	* @see pbuf_free()
idinor	0:dcf3c92487ca	664	*/
idinor	0:dcf3c92487ca	665	static void
idinor	0:dcf3c92487ca	666	etharp_arp_input(struct netif netif, struct eth_addr ethaddr, struct pbuf *p)
idinor	0:dcf3c92487ca	667	{
idinor	0:dcf3c92487ca	668	struct etharp_hdr *hdr;
idinor	0:dcf3c92487ca	669	struct eth_hdr *ethhdr;
idinor	0:dcf3c92487ca	670	/* these are aligned properly, whereas the ARP header fields might not be */
idinor	0:dcf3c92487ca	671	ip_addr_t sipaddr, dipaddr;
idinor	0:dcf3c92487ca	672	u8_t for_us;
idinor	0:dcf3c92487ca	673	#if LWIP_AUTOIP
idinor	0:dcf3c92487ca	674	const u8_t * ethdst_hwaddr;
idinor	0:dcf3c92487ca	675	#endif /* LWIP_AUTOIP */
idinor	0:dcf3c92487ca	676
idinor	0:dcf3c92487ca	677	LWIP_ERROR("netif != NULL", (netif != NULL), return;);
idinor	0:dcf3c92487ca	678
idinor	0:dcf3c92487ca	679	/* drop short ARP packets: we have to check for p->len instead of p->tot_len here
idinor	0:dcf3c92487ca	680	since a struct etharp_hdr is pointed to p->payload, so it musn't be chained! */
idinor	0:dcf3c92487ca	681	if (p->len < SIZEOF_ETHARP_PACKET) {
idinor	0:dcf3c92487ca	682	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_WARNING,
idinor	0:dcf3c92487ca	683	("etharp_arp_input: packet dropped, too short (%"S16_F"/%"S16_F")\n", p->tot_len,
idinor	0:dcf3c92487ca	684	(s16_t)SIZEOF_ETHARP_PACKET));
idinor	0:dcf3c92487ca	685	ETHARP_STATS_INC(etharp.lenerr);
idinor	0:dcf3c92487ca	686	ETHARP_STATS_INC(etharp.drop);
idinor	0:dcf3c92487ca	687	pbuf_free(p);
idinor	0:dcf3c92487ca	688	return;
idinor	0:dcf3c92487ca	689	}
idinor	0:dcf3c92487ca	690
idinor	0:dcf3c92487ca	691	ethhdr = (struct eth_hdr *)p->payload;
idinor	0:dcf3c92487ca	692	hdr = (struct etharp_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
idinor	0:dcf3c92487ca	693	#if ETHARP_SUPPORT_VLAN
idinor	0:dcf3c92487ca	694	if (ethhdr->type == ETHTYPE_VLAN) {
idinor	0:dcf3c92487ca	695	hdr = (struct etharp_hdr )(((u8_t)ethhdr) + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
idinor	0:dcf3c92487ca	696	}
idinor	0:dcf3c92487ca	697	#endif /* ETHARP_SUPPORT_VLAN */
idinor	0:dcf3c92487ca	698
idinor	0:dcf3c92487ca	699	/* RFC 826 "Packet Reception": */
idinor	0:dcf3c92487ca	700	if ((hdr->hwtype != PP_HTONS(HWTYPE_ETHERNET)) \|\|
idinor	0:dcf3c92487ca	701	(hdr->hwlen != ETHARP_HWADDR_LEN) \|\|
idinor	0:dcf3c92487ca	702	(hdr->protolen != sizeof(ip_addr_t)) \|\|
idinor	0:dcf3c92487ca	703	(hdr->proto != PP_HTONS(ETHTYPE_IP)) \|\|
idinor	0:dcf3c92487ca	704	(ethhdr->type != PP_HTONS(ETHTYPE_ARP))) {
idinor	0:dcf3c92487ca	705	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_WARNING,
idinor	0:dcf3c92487ca	706	("etharp_arp_input: packet dropped, wrong hw type, hwlen, proto, protolen or ethernet type (%"U16_F"/%"U16_F"/%"U16_F"/%"U16_F"/%"U16_F")\n",
idinor	0:dcf3c92487ca	707	hdr->hwtype, hdr->hwlen, hdr->proto, hdr->protolen, ethhdr->type));
idinor	0:dcf3c92487ca	708	ETHARP_STATS_INC(etharp.proterr);
idinor	0:dcf3c92487ca	709	ETHARP_STATS_INC(etharp.drop);
idinor	0:dcf3c92487ca	710	pbuf_free(p);
idinor	0:dcf3c92487ca	711	return;
idinor	0:dcf3c92487ca	712	}
idinor	0:dcf3c92487ca	713	ETHARP_STATS_INC(etharp.recv);
idinor	0:dcf3c92487ca	714
idinor	0:dcf3c92487ca	715	#if LWIP_AUTOIP
idinor	0:dcf3c92487ca	716	/* We have to check if a host already has configured our random
idinor	0:dcf3c92487ca	717	* created link local address and continously check if there is
idinor	0:dcf3c92487ca	718	* a host with this IP-address so we can detect collisions */
idinor	0:dcf3c92487ca	719	autoip_arp_reply(netif, hdr);
idinor	0:dcf3c92487ca	720	#endif /* LWIP_AUTOIP */
idinor	0:dcf3c92487ca	721
idinor	0:dcf3c92487ca	722	/* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
idinor	0:dcf3c92487ca	723	* structure packing (not using structure copy which breaks strict-aliasing rules). */
idinor	0:dcf3c92487ca	724	IPADDR2_COPY(&sipaddr, &hdr->sipaddr);
idinor	0:dcf3c92487ca	725	IPADDR2_COPY(&dipaddr, &hdr->dipaddr);
idinor	0:dcf3c92487ca	726
idinor	0:dcf3c92487ca	727	/* this interface is not configured? */
idinor	0:dcf3c92487ca	728	if (ip_addr_isany(&netif->ip_addr)) {
idinor	0:dcf3c92487ca	729	for_us = 0;
idinor	0:dcf3c92487ca	730	} else {
idinor	0:dcf3c92487ca	731	/* ARP packet directed to us? */
idinor	0:dcf3c92487ca	732	for_us = (u8_t)ip_addr_cmp(&dipaddr, &(netif->ip_addr));
idinor	0:dcf3c92487ca	733	}
idinor	0:dcf3c92487ca	734
idinor	0:dcf3c92487ca	735	/* ARP message directed to us?
idinor	0:dcf3c92487ca	736	-> add IP address in ARP cache; assume requester wants to talk to us,
idinor	0:dcf3c92487ca	737	can result in directly sending the queued packets for this host.
idinor	0:dcf3c92487ca	738	ARP message not directed to us?
idinor	0:dcf3c92487ca	739	-> update the source IP address in the cache, if present */
idinor	0:dcf3c92487ca	740	update_arp_entry(netif, &sipaddr, &(hdr->shwaddr),
idinor	0:dcf3c92487ca	741	for_us ? ETHARP_FLAG_TRY_HARD : ETHARP_FLAG_FIND_ONLY);
idinor	0:dcf3c92487ca	742
idinor	0:dcf3c92487ca	743	/* now act on the message itself */
idinor	0:dcf3c92487ca	744	switch (hdr->opcode) {
idinor	0:dcf3c92487ca	745	/* ARP request? */
idinor	0:dcf3c92487ca	746	case PP_HTONS(ARP_REQUEST):
idinor	0:dcf3c92487ca	747	/* ARP request. If it asked for our address, we send out a
idinor	0:dcf3c92487ca	748	* reply. In any case, we time-stamp any existing ARP entry,
idinor	0:dcf3c92487ca	749	* and possiby send out an IP packet that was queued on it. */
idinor	0:dcf3c92487ca	750
idinor	0:dcf3c92487ca	751	LWIP_DEBUGF (ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP request\n"));
idinor	0:dcf3c92487ca	752	/* ARP request for our address? */
idinor	0:dcf3c92487ca	753	if (for_us) {
idinor	0:dcf3c92487ca	754
idinor	0:dcf3c92487ca	755	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: replying to ARP request for our IP address\n"));
idinor	0:dcf3c92487ca	756	/* Re-use pbuf to send ARP reply.
idinor	0:dcf3c92487ca	757	Since we are re-using an existing pbuf, we can't call etharp_raw since
idinor	0:dcf3c92487ca	758	that would allocate a new pbuf. */
idinor	0:dcf3c92487ca	759	hdr->opcode = htons(ARP_REPLY);
idinor	0:dcf3c92487ca	760
idinor	0:dcf3c92487ca	761	IPADDR2_COPY(&hdr->dipaddr, &hdr->sipaddr);
idinor	0:dcf3c92487ca	762	IPADDR2_COPY(&hdr->sipaddr, &netif->ip_addr);
idinor	0:dcf3c92487ca	763
idinor	0:dcf3c92487ca	764	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
idinor	0:dcf3c92487ca	765	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
idinor	0:dcf3c92487ca	766	#if LWIP_AUTOIP
idinor	0:dcf3c92487ca	767	/* If we are using Link-Local, all ARP packets that contain a Link-Local
idinor	0:dcf3c92487ca	768	* 'sender IP address' MUST be sent using link-layer broadcast instead of
idinor	0:dcf3c92487ca	769	* link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
idinor	0:dcf3c92487ca	770	ethdst_hwaddr = ip_addr_islinklocal(&netif->ip_addr) ? (u8_t*)(ethbroadcast.addr) : hdr->shwaddr.addr;
idinor	0:dcf3c92487ca	771	#endif /* LWIP_AUTOIP */
idinor	0:dcf3c92487ca	772
idinor	0:dcf3c92487ca	773	ETHADDR16_COPY(&hdr->dhwaddr, &hdr->shwaddr);
idinor	0:dcf3c92487ca	774	#if LWIP_AUTOIP
idinor	0:dcf3c92487ca	775	ETHADDR16_COPY(&ethhdr->dest, ethdst_hwaddr);
idinor	0:dcf3c92487ca	776	#else /* LWIP_AUTOIP */
idinor	0:dcf3c92487ca	777	ETHADDR16_COPY(&ethhdr->dest, &hdr->shwaddr);
idinor	0:dcf3c92487ca	778	#endif /* LWIP_AUTOIP */
idinor	0:dcf3c92487ca	779	ETHADDR16_COPY(&hdr->shwaddr, ethaddr);
idinor	0:dcf3c92487ca	780	ETHADDR16_COPY(&ethhdr->src, ethaddr);
idinor	0:dcf3c92487ca	781
idinor	0:dcf3c92487ca	782	/* hwtype, hwaddr_len, proto, protolen and the type in the ethernet header
idinor	0:dcf3c92487ca	783	are already correct, we tested that before */
idinor	0:dcf3c92487ca	784
idinor	0:dcf3c92487ca	785	/* return ARP reply */
idinor	0:dcf3c92487ca	786	netif->linkoutput(netif, p);
idinor	0:dcf3c92487ca	787	/* we are not configured? */
idinor	0:dcf3c92487ca	788	} else if (ip_addr_isany(&netif->ip_addr)) {
idinor	0:dcf3c92487ca	789	/* { for_us == 0 and netif->ip_addr.addr == 0 } */
idinor	0:dcf3c92487ca	790	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: we are unconfigured, ARP request ignored.\n"));
idinor	0:dcf3c92487ca	791	/* request was not directed to us */
idinor	0:dcf3c92487ca	792	} else {
idinor	0:dcf3c92487ca	793	/* { for_us == 0 and netif->ip_addr.addr != 0 } */
idinor	0:dcf3c92487ca	794	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: ARP request was not for us.\n"));
idinor	0:dcf3c92487ca	795	}
idinor	0:dcf3c92487ca	796	break;
idinor	0:dcf3c92487ca	797	case PP_HTONS(ARP_REPLY):
idinor	0:dcf3c92487ca	798	/* ARP reply. We already updated the ARP cache earlier. */
idinor	0:dcf3c92487ca	799	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP reply\n"));
idinor	0:dcf3c92487ca	800	#if (LWIP_DHCP && DHCP_DOES_ARP_CHECK)
idinor	0:dcf3c92487ca	801	/* DHCP wants to know about ARP replies from any host with an
idinor	0:dcf3c92487ca	802	* IP address also offered to us by the DHCP server. We do not
idinor	0:dcf3c92487ca	803	* want to take a duplicate IP address on a single network.
idinor	0:dcf3c92487ca	804	* @todo How should we handle redundant (fail-over) interfaces? */
idinor	0:dcf3c92487ca	805	dhcp_arp_reply(netif, &sipaddr);
idinor	0:dcf3c92487ca	806	#endif /* (LWIP_DHCP && DHCP_DOES_ARP_CHECK) */
idinor	0:dcf3c92487ca	807	break;
idinor	0:dcf3c92487ca	808	default:
idinor	0:dcf3c92487ca	809	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: ARP unknown opcode type %"S16_F"\n", htons(hdr->opcode)));
idinor	0:dcf3c92487ca	810	ETHARP_STATS_INC(etharp.err);
idinor	0:dcf3c92487ca	811	break;
idinor	0:dcf3c92487ca	812	}
idinor	0:dcf3c92487ca	813	/* free ARP packet */
idinor	0:dcf3c92487ca	814	pbuf_free(p);
idinor	0:dcf3c92487ca	815	}
idinor	0:dcf3c92487ca	816
idinor	0:dcf3c92487ca	817	/**
idinor	0:dcf3c92487ca	818	* Resolve and fill-in Ethernet address header for outgoing IP packet.
idinor	0:dcf3c92487ca	819	*
idinor	0:dcf3c92487ca	820	* For IP multicast and broadcast, corresponding Ethernet addresses
idinor	0:dcf3c92487ca	821	* are selected and the packet is transmitted on the link.
idinor	0:dcf3c92487ca	822	*
idinor	0:dcf3c92487ca	823	* For unicast addresses, the packet is submitted to etharp_query(). In
idinor	0:dcf3c92487ca	824	* case the IP address is outside the local network, the IP address of
idinor	0:dcf3c92487ca	825	* the gateway is used.
idinor	0:dcf3c92487ca	826	*
idinor	0:dcf3c92487ca	827	* @param netif The lwIP network interface which the IP packet will be sent on.
idinor	0:dcf3c92487ca	828	* @param q The pbuf(s) containing the IP packet to be sent.
idinor	0:dcf3c92487ca	829	* @param ipaddr The IP address of the packet destination.
idinor	0:dcf3c92487ca	830	*
idinor	0:dcf3c92487ca	831	* @return
idinor	0:dcf3c92487ca	832	* - ERR_RTE No route to destination (no gateway to external networks),
idinor	0:dcf3c92487ca	833	* or the return type of either etharp_query() or etharp_send_ip().
idinor	0:dcf3c92487ca	834	*/
idinor	0:dcf3c92487ca	835	err_t
idinor	0:dcf3c92487ca	836	etharp_output(struct netif netif, struct pbuf q, ip_addr_t *ipaddr)
idinor	0:dcf3c92487ca	837	{
idinor	0:dcf3c92487ca	838	struct eth_addr *dest, mcastaddr;
idinor	0:dcf3c92487ca	839
idinor	0:dcf3c92487ca	840	/* make room for Ethernet header - should not fail */
idinor	0:dcf3c92487ca	841	if (pbuf_header(q, sizeof(struct eth_hdr)) != 0) {
idinor	0:dcf3c92487ca	842	/* bail out */
idinor	0:dcf3c92487ca	843	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_SERIOUS,
idinor	0:dcf3c92487ca	844	("etharp_output: could not allocate room for header.\n"));
idinor	0:dcf3c92487ca	845	LINK_STATS_INC(link.lenerr);
idinor	0:dcf3c92487ca	846	return ERR_BUF;
idinor	0:dcf3c92487ca	847	}
idinor	0:dcf3c92487ca	848
idinor	0:dcf3c92487ca	849	/* assume unresolved Ethernet address */
idinor	0:dcf3c92487ca	850	dest = NULL;
idinor	0:dcf3c92487ca	851	/* Determine on destination hardware address. Broadcasts and multicasts
idinor	0:dcf3c92487ca	852	* are special, other IP addresses are looked up in the ARP table. */
idinor	0:dcf3c92487ca	853
idinor	0:dcf3c92487ca	854	/* broadcast destination IP address? */
idinor	0:dcf3c92487ca	855	if (ip_addr_isbroadcast(ipaddr, netif)) {
idinor	0:dcf3c92487ca	856	/* broadcast on Ethernet also */
idinor	0:dcf3c92487ca	857	dest = (struct eth_addr *)&ethbroadcast;
idinor	0:dcf3c92487ca	858	/* multicast destination IP address? */
idinor	0:dcf3c92487ca	859	} else if (ip_addr_ismulticast(ipaddr)) {
idinor	0:dcf3c92487ca	860	/* Hash IP multicast address to MAC address.*/
idinor	0:dcf3c92487ca	861	mcastaddr.addr[0] = 0x01;
idinor	0:dcf3c92487ca	862	mcastaddr.addr[1] = 0x00;
idinor	0:dcf3c92487ca	863	mcastaddr.addr[2] = 0x5e;
idinor	0:dcf3c92487ca	864	mcastaddr.addr[3] = ip4_addr2(ipaddr) & 0x7f;
idinor	0:dcf3c92487ca	865	mcastaddr.addr[4] = ip4_addr3(ipaddr);
idinor	0:dcf3c92487ca	866	mcastaddr.addr[5] = ip4_addr4(ipaddr);
idinor	0:dcf3c92487ca	867	/* destination Ethernet address is multicast */
idinor	0:dcf3c92487ca	868	dest = &mcastaddr;
idinor	0:dcf3c92487ca	869	/* unicast destination IP address? */
idinor	0:dcf3c92487ca	870	} else {
idinor	0:dcf3c92487ca	871	/* outside local network? */
idinor	0:dcf3c92487ca	872	if (!ip_addr_netcmp(ipaddr, &(netif->ip_addr), &(netif->netmask)) &&
idinor	0:dcf3c92487ca	873	!ip_addr_islinklocal(ipaddr)) {
idinor	0:dcf3c92487ca	874	/* interface has default gateway? */
idinor	0:dcf3c92487ca	875	if (!ip_addr_isany(&netif->gw)) {
idinor	0:dcf3c92487ca	876	/* send to hardware address of default gateway IP address */
idinor	0:dcf3c92487ca	877	ipaddr = &(netif->gw);
idinor	0:dcf3c92487ca	878	/* no default gateway available */
idinor	0:dcf3c92487ca	879	} else {
idinor	0:dcf3c92487ca	880	/* no route to destination error (default gateway missing) */
idinor	0:dcf3c92487ca	881	return ERR_RTE;
idinor	0:dcf3c92487ca	882	}
idinor	0:dcf3c92487ca	883	}
idinor	0:dcf3c92487ca	884	#if LWIP_NETIF_HWADDRHINT
idinor	0:dcf3c92487ca	885	if (netif->addr_hint != NULL) {
idinor	0:dcf3c92487ca	886	/* per-pcb cached entry was given */
idinor	0:dcf3c92487ca	887	u8_t etharp_cached_entry = *(netif->addr_hint);
idinor	0:dcf3c92487ca	888	if (etharp_cached_entry < ARP_TABLE_SIZE) {
idinor	0:dcf3c92487ca	889	#endif /* LWIP_NETIF_HWADDRHINT */
idinor	0:dcf3c92487ca	890	if ((arp_table[etharp_cached_entry].state == ETHARP_STATE_STABLE) &&
idinor	0:dcf3c92487ca	891	(ip_addr_cmp(ipaddr, &arp_table[etharp_cached_entry].ipaddr))) {
idinor	0:dcf3c92487ca	892	/* the per-pcb-cached entry is stable and the right one! */
idinor	0:dcf3c92487ca	893	ETHARP_STATS_INC(etharp.cachehit);
idinor	0:dcf3c92487ca	894	return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr),
idinor	0:dcf3c92487ca	895	&arp_table[etharp_cached_entry].ethaddr);
idinor	0:dcf3c92487ca	896	}
idinor	0:dcf3c92487ca	897	#if LWIP_NETIF_HWADDRHINT
idinor	0:dcf3c92487ca	898	}
idinor	0:dcf3c92487ca	899	}
idinor	0:dcf3c92487ca	900	#endif /* LWIP_NETIF_HWADDRHINT */
idinor	0:dcf3c92487ca	901	/* queue on destination Ethernet address belonging to ipaddr */
idinor	0:dcf3c92487ca	902	return etharp_query(netif, ipaddr, q);
idinor	0:dcf3c92487ca	903	}
idinor	0:dcf3c92487ca	904
idinor	0:dcf3c92487ca	905	/* continuation for multicast/broadcast destinations */
idinor	0:dcf3c92487ca	906	/* obtain source Ethernet address of the given interface */
idinor	0:dcf3c92487ca	907	/* send packet directly on the link */
idinor	0:dcf3c92487ca	908	return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr), dest);
idinor	0:dcf3c92487ca	909	}
idinor	0:dcf3c92487ca	910
idinor	0:dcf3c92487ca	911	/**
idinor	0:dcf3c92487ca	912	* Send an ARP request for the given IP address and/or queue a packet.
idinor	0:dcf3c92487ca	913	*
idinor	0:dcf3c92487ca	914	* If the IP address was not yet in the cache, a pending ARP cache entry
idinor	0:dcf3c92487ca	915	* is added and an ARP request is sent for the given address. The packet
idinor	0:dcf3c92487ca	916	* is queued on this entry.
idinor	0:dcf3c92487ca	917	*
idinor	0:dcf3c92487ca	918	* If the IP address was already pending in the cache, a new ARP request
idinor	0:dcf3c92487ca	919	* is sent for the given address. The packet is queued on this entry.
idinor	0:dcf3c92487ca	920	*
idinor	0:dcf3c92487ca	921	* If the IP address was already stable in the cache, and a packet is
idinor	0:dcf3c92487ca	922	* given, it is directly sent and no ARP request is sent out.
idinor	0:dcf3c92487ca	923	*
idinor	0:dcf3c92487ca	924	* If the IP address was already stable in the cache, and no packet is
idinor	0:dcf3c92487ca	925	* given, an ARP request is sent out.
idinor	0:dcf3c92487ca	926	*
idinor	0:dcf3c92487ca	927	* @param netif The lwIP network interface on which ipaddr
idinor	0:dcf3c92487ca	928	* must be queried for.
idinor	0:dcf3c92487ca	929	* @param ipaddr The IP address to be resolved.
idinor	0:dcf3c92487ca	930	* @param q If non-NULL, a pbuf that must be delivered to the IP address.
idinor	0:dcf3c92487ca	931	* q is not freed by this function.
idinor	0:dcf3c92487ca	932	*
idinor	0:dcf3c92487ca	933	* @note q must only be ONE packet, not a packet queue!
idinor	0:dcf3c92487ca	934	*
idinor	0:dcf3c92487ca	935	* @return
idinor	0:dcf3c92487ca	936	* - ERR_BUF Could not make room for Ethernet header.
idinor	0:dcf3c92487ca	937	* - ERR_MEM Hardware address unknown, and no more ARP entries available
idinor	0:dcf3c92487ca	938	* to query for address or queue the packet.
idinor	0:dcf3c92487ca	939	* - ERR_MEM Could not queue packet due to memory shortage.
idinor	0:dcf3c92487ca	940	* - ERR_RTE No route to destination (no gateway to external networks).
idinor	0:dcf3c92487ca	941	* - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
idinor	0:dcf3c92487ca	942	*
idinor	0:dcf3c92487ca	943	*/
idinor	0:dcf3c92487ca	944	err_t
idinor	0:dcf3c92487ca	945	etharp_query(struct netif netif, ip_addr_t ipaddr, struct pbuf *q)
idinor	0:dcf3c92487ca	946	{
idinor	0:dcf3c92487ca	947	struct eth_addr * srcaddr = (struct eth_addr *)netif->hwaddr;
idinor	0:dcf3c92487ca	948	err_t result = ERR_MEM;
idinor	0:dcf3c92487ca	949	s8_t i; /* ARP entry index */
idinor	0:dcf3c92487ca	950
idinor	0:dcf3c92487ca	951	/* non-unicast address? */
idinor	0:dcf3c92487ca	952	if (ip_addr_isbroadcast(ipaddr, netif) \|\|
idinor	0:dcf3c92487ca	953	ip_addr_ismulticast(ipaddr) \|\|
idinor	0:dcf3c92487ca	954	ip_addr_isany(ipaddr)) {
idinor	0:dcf3c92487ca	955	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: will not add non-unicast IP address to ARP cache\n"));
idinor	0:dcf3c92487ca	956	return ERR_ARG;
idinor	0:dcf3c92487ca	957	}
idinor	0:dcf3c92487ca	958
idinor	0:dcf3c92487ca	959	/* find entry in ARP cache, ask to create entry if queueing packet */
idinor	0:dcf3c92487ca	960	i = find_entry(ipaddr, ETHARP_FLAG_TRY_HARD);
idinor	0:dcf3c92487ca	961
idinor	0:dcf3c92487ca	962	/* could not find or create entry? */
idinor	0:dcf3c92487ca	963	if (i < 0) {
idinor	0:dcf3c92487ca	964	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: could not create ARP entry\n"));
idinor	0:dcf3c92487ca	965	if (q) {
idinor	0:dcf3c92487ca	966	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: packet dropped\n"));
idinor	0:dcf3c92487ca	967	ETHARP_STATS_INC(etharp.memerr);
idinor	0:dcf3c92487ca	968	}
idinor	0:dcf3c92487ca	969	return (err_t)i;
idinor	0:dcf3c92487ca	970	}
idinor	0:dcf3c92487ca	971
idinor	0:dcf3c92487ca	972	/* mark a fresh entry as pending (we just sent a request) */
idinor	0:dcf3c92487ca	973	if (arp_table[i].state == ETHARP_STATE_EMPTY) {
idinor	0:dcf3c92487ca	974	arp_table[i].state = ETHARP_STATE_PENDING;
idinor	0:dcf3c92487ca	975	}
idinor	0:dcf3c92487ca	976
idinor	0:dcf3c92487ca	977	/* { i is either a STABLE or (new or existing) PENDING entry } */
idinor	0:dcf3c92487ca	978	LWIP_ASSERT("arp_table[i].state == PENDING or STABLE",
idinor	0:dcf3c92487ca	979	((arp_table[i].state == ETHARP_STATE_PENDING) \|\|
idinor	0:dcf3c92487ca	980	(arp_table[i].state == ETHARP_STATE_STABLE)));
idinor	0:dcf3c92487ca	981
idinor	0:dcf3c92487ca	982	/* do we have a pending entry? or an implicit query request? */
idinor	0:dcf3c92487ca	983	if ((arp_table[i].state == ETHARP_STATE_PENDING) \|\| (q == NULL)) {
idinor	0:dcf3c92487ca	984	/* try to resolve it; send out ARP request */
idinor	0:dcf3c92487ca	985	result = etharp_request(netif, ipaddr);
idinor	0:dcf3c92487ca	986	if (result != ERR_OK) {
idinor	0:dcf3c92487ca	987	/* ARP request couldn't be sent */
idinor	0:dcf3c92487ca	988	/* We don't re-send arp request in etharp_tmr, but we still queue packets,
idinor	0:dcf3c92487ca	989	since this failure could be temporary, and the next packet calling
idinor	0:dcf3c92487ca	990	etharp_query again could lead to sending the queued packets. */
idinor	0:dcf3c92487ca	991	}
idinor	0:dcf3c92487ca	992	if (q == NULL) {
idinor	0:dcf3c92487ca	993	return result;
idinor	0:dcf3c92487ca	994	}
idinor	0:dcf3c92487ca	995	}
idinor	0:dcf3c92487ca	996
idinor	0:dcf3c92487ca	997	/* packet given? */
idinor	0:dcf3c92487ca	998	LWIP_ASSERT("q != NULL", q != NULL);
idinor	0:dcf3c92487ca	999	/* stable entry? */
idinor	0:dcf3c92487ca	1000	if (arp_table[i].state == ETHARP_STATE_STABLE) {
idinor	0:dcf3c92487ca	1001	/* we have a valid IP->Ethernet address mapping */
idinor	0:dcf3c92487ca	1002	ETHARP_SET_HINT(netif, i);
idinor	0:dcf3c92487ca	1003	/* send the packet */
idinor	0:dcf3c92487ca	1004	result = etharp_send_ip(netif, q, srcaddr, &(arp_table[i].ethaddr));
idinor	0:dcf3c92487ca	1005	/* pending entry? (either just created or already pending */
idinor	0:dcf3c92487ca	1006	} else if (arp_table[i].state == ETHARP_STATE_PENDING) {
idinor	0:dcf3c92487ca	1007	#if ARP_QUEUEING /* queue the given q packet */
idinor	0:dcf3c92487ca	1008	struct pbuf *p;
idinor	0:dcf3c92487ca	1009	int copy_needed = 0;
idinor	0:dcf3c92487ca	1010	/* IF q includes a PBUF_REF, PBUF_POOL or PBUF_RAM, we have no choice but
idinor	0:dcf3c92487ca	1011	* to copy the whole queue into a new PBUF_RAM (see bug #11400)
idinor	0:dcf3c92487ca	1012	* PBUF_ROMs can be left as they are, since ROM must not get changed. */
idinor	0:dcf3c92487ca	1013	p = q;
idinor	0:dcf3c92487ca	1014	while (p) {
idinor	0:dcf3c92487ca	1015	LWIP_ASSERT("no packet queues allowed!", (p->len != p->tot_len) \|\| (p->next == 0));
idinor	0:dcf3c92487ca	1016	if(p->type != PBUF_ROM) {
idinor	0:dcf3c92487ca	1017	copy_needed = 1;
idinor	0:dcf3c92487ca	1018	break;
idinor	0:dcf3c92487ca	1019	}
idinor	0:dcf3c92487ca	1020	p = p->next;
idinor	0:dcf3c92487ca	1021	}
idinor	0:dcf3c92487ca	1022	if(copy_needed) {
idinor	0:dcf3c92487ca	1023	/* copy the whole packet into new pbufs */
idinor	0:dcf3c92487ca	1024	p = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
idinor	0:dcf3c92487ca	1025	if(p != NULL) {
idinor	0:dcf3c92487ca	1026	if (pbuf_copy(p, q) != ERR_OK) {
idinor	0:dcf3c92487ca	1027	pbuf_free(p);
idinor	0:dcf3c92487ca	1028	p = NULL;
idinor	0:dcf3c92487ca	1029	}
idinor	0:dcf3c92487ca	1030	}
idinor	0:dcf3c92487ca	1031	} else {
idinor	0:dcf3c92487ca	1032	/* referencing the old pbuf is enough */
idinor	0:dcf3c92487ca	1033	p = q;
idinor	0:dcf3c92487ca	1034	pbuf_ref(p);
idinor	0:dcf3c92487ca	1035	}
idinor	0:dcf3c92487ca	1036	/* packet could be taken over? */
idinor	0:dcf3c92487ca	1037	if (p != NULL) {
idinor	0:dcf3c92487ca	1038	/* queue packet ... */
idinor	0:dcf3c92487ca	1039	struct etharp_q_entry *new_entry;
idinor	0:dcf3c92487ca	1040	/* allocate a new arp queue entry */
idinor	0:dcf3c92487ca	1041	new_entry = (struct etharp_q_entry *)memp_malloc(MEMP_ARP_QUEUE);
idinor	0:dcf3c92487ca	1042	if (new_entry != NULL) {
idinor	0:dcf3c92487ca	1043	new_entry->next = 0;
idinor	0:dcf3c92487ca	1044	new_entry->p = p;
idinor	0:dcf3c92487ca	1045	if(arp_table[i].q != NULL) {
idinor	0:dcf3c92487ca	1046	/* queue was already existent, append the new entry to the end */
idinor	0:dcf3c92487ca	1047	struct etharp_q_entry *r;
idinor	0:dcf3c92487ca	1048	r = arp_table[i].q;
idinor	0:dcf3c92487ca	1049	while (r->next != NULL) {
idinor	0:dcf3c92487ca	1050	r = r->next;
idinor	0:dcf3c92487ca	1051	}
idinor	0:dcf3c92487ca	1052	r->next = new_entry;
idinor	0:dcf3c92487ca	1053	} else {
idinor	0:dcf3c92487ca	1054	/* queue did not exist, first item in queue */
idinor	0:dcf3c92487ca	1055	arp_table[i].q = new_entry;
idinor	0:dcf3c92487ca	1056	}
idinor	0:dcf3c92487ca	1057	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: queued packet %p on ARP entry %"S16_F"\n", (void *)q, (s16_t)i));
idinor	0:dcf3c92487ca	1058	result = ERR_OK;
idinor	0:dcf3c92487ca	1059	} else {
idinor	0:dcf3c92487ca	1060	/* the pool MEMP_ARP_QUEUE is empty */
idinor	0:dcf3c92487ca	1061	pbuf_free(p);
idinor	0:dcf3c92487ca	1062	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: could not queue a copy of PBUF_REF packet %p (out of memory)\n", (void *)q));
idinor	0:dcf3c92487ca	1063	/* { result == ERR_MEM } through initialization */
idinor	0:dcf3c92487ca	1064	}
idinor	0:dcf3c92487ca	1065	} else {
idinor	0:dcf3c92487ca	1066	ETHARP_STATS_INC(etharp.memerr);
idinor	0:dcf3c92487ca	1067	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: could not queue a copy of PBUF_REF packet %p (out of memory)\n", (void *)q));
idinor	0:dcf3c92487ca	1068	/* { result == ERR_MEM } through initialization */
idinor	0:dcf3c92487ca	1069	}
idinor	0:dcf3c92487ca	1070	#else /* ARP_QUEUEING */
idinor	0:dcf3c92487ca	1071	/* q && state == PENDING && ARP_QUEUEING == 0 => result = ERR_MEM */
idinor	0:dcf3c92487ca	1072	/* { result == ERR_MEM } through initialization */
idinor	0:dcf3c92487ca	1073	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: Ethernet destination address unknown, queueing disabled, packet %p dropped\n", (void *)q));
idinor	0:dcf3c92487ca	1074	#endif /* ARP_QUEUEING */
idinor	0:dcf3c92487ca	1075	}
idinor	0:dcf3c92487ca	1076	return result;
idinor	0:dcf3c92487ca	1077	}
idinor	0:dcf3c92487ca	1078
idinor	0:dcf3c92487ca	1079	/**
idinor	0:dcf3c92487ca	1080	* Send a raw ARP packet (opcode and all addresses can be modified)
idinor	0:dcf3c92487ca	1081	*
idinor	0:dcf3c92487ca	1082	* @param netif the lwip network interface on which to send the ARP packet
idinor	0:dcf3c92487ca	1083	* @param ethsrc_addr the source MAC address for the ethernet header
idinor	0:dcf3c92487ca	1084	* @param ethdst_addr the destination MAC address for the ethernet header
idinor	0:dcf3c92487ca	1085	* @param hwsrc_addr the source MAC address for the ARP protocol header
idinor	0:dcf3c92487ca	1086	* @param ipsrc_addr the source IP address for the ARP protocol header
idinor	0:dcf3c92487ca	1087	* @param hwdst_addr the destination MAC address for the ARP protocol header
idinor	0:dcf3c92487ca	1088	* @param ipdst_addr the destination IP address for the ARP protocol header
idinor	0:dcf3c92487ca	1089	* @param opcode the type of the ARP packet
idinor	0:dcf3c92487ca	1090	* @return ERR_OK if the ARP packet has been sent
idinor	0:dcf3c92487ca	1091	* ERR_MEM if the ARP packet couldn't be allocated
idinor	0:dcf3c92487ca	1092	* any other err_t on failure
idinor	0:dcf3c92487ca	1093	*/
idinor	0:dcf3c92487ca	1094	#if !LWIP_AUTOIP
idinor	0:dcf3c92487ca	1095	static
idinor	0:dcf3c92487ca	1096	#endif /* LWIP_AUTOIP */
idinor	0:dcf3c92487ca	1097	err_t
idinor	0:dcf3c92487ca	1098	etharp_raw(struct netif netif, const struct eth_addr ethsrc_addr,
idinor	0:dcf3c92487ca	1099	const struct eth_addr *ethdst_addr,
idinor	0:dcf3c92487ca	1100	const struct eth_addr hwsrc_addr, const ip_addr_t ipsrc_addr,
idinor	0:dcf3c92487ca	1101	const struct eth_addr hwdst_addr, const ip_addr_t ipdst_addr,
idinor	0:dcf3c92487ca	1102	const u16_t opcode)
idinor	0:dcf3c92487ca	1103	{
idinor	0:dcf3c92487ca	1104	struct pbuf *p;
idinor	0:dcf3c92487ca	1105	err_t result = ERR_OK;
idinor	0:dcf3c92487ca	1106	struct eth_hdr *ethhdr;
idinor	0:dcf3c92487ca	1107	struct etharp_hdr *hdr;
idinor	0:dcf3c92487ca	1108	#if LWIP_AUTOIP
idinor	0:dcf3c92487ca	1109	const u8_t * ethdst_hwaddr;
idinor	0:dcf3c92487ca	1110	#endif /* LWIP_AUTOIP */
idinor	0:dcf3c92487ca	1111
idinor	0:dcf3c92487ca	1112	/* allocate a pbuf for the outgoing ARP request packet */
idinor	0:dcf3c92487ca	1113	p = pbuf_alloc(PBUF_RAW, SIZEOF_ETHARP_PACKET, PBUF_RAM);
idinor	0:dcf3c92487ca	1114	/* could allocate a pbuf for an ARP request? */
idinor	0:dcf3c92487ca	1115	if (p == NULL) {
idinor	0:dcf3c92487ca	1116	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_SERIOUS,
idinor	0:dcf3c92487ca	1117	("etharp_raw: could not allocate pbuf for ARP request.\n"));
idinor	0:dcf3c92487ca	1118	ETHARP_STATS_INC(etharp.memerr);
idinor	0:dcf3c92487ca	1119	return ERR_MEM;
idinor	0:dcf3c92487ca	1120	}
idinor	0:dcf3c92487ca	1121	LWIP_ASSERT("check that first pbuf can hold struct etharp_hdr",
idinor	0:dcf3c92487ca	1122	(p->len >= SIZEOF_ETHARP_PACKET));
idinor	0:dcf3c92487ca	1123
idinor	0:dcf3c92487ca	1124	ethhdr = (struct eth_hdr *)p->payload;
idinor	0:dcf3c92487ca	1125	hdr = (struct etharp_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
idinor	0:dcf3c92487ca	1126	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_raw: sending raw ARP packet.\n"));
idinor	0:dcf3c92487ca	1127	hdr->opcode = htons(opcode);
idinor	0:dcf3c92487ca	1128
idinor	0:dcf3c92487ca	1129	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
idinor	0:dcf3c92487ca	1130	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
idinor	0:dcf3c92487ca	1131	#if LWIP_AUTOIP
idinor	0:dcf3c92487ca	1132	/* If we are using Link-Local, all ARP packets that contain a Link-Local
idinor	0:dcf3c92487ca	1133	* 'sender IP address' MUST be sent using link-layer broadcast instead of
idinor	0:dcf3c92487ca	1134	* link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
idinor	0:dcf3c92487ca	1135	ethdst_hwaddr = ip_addr_islinklocal(ipsrc_addr) ? (u8_t*)(ethbroadcast.addr) : ethdst_addr->addr;
idinor	0:dcf3c92487ca	1136	#endif /* LWIP_AUTOIP */
idinor	0:dcf3c92487ca	1137	/* Write the ARP MAC-Addresses */
idinor	0:dcf3c92487ca	1138	ETHADDR16_COPY(&hdr->shwaddr, hwsrc_addr);
idinor	0:dcf3c92487ca	1139	ETHADDR16_COPY(&hdr->dhwaddr, hwdst_addr);
idinor	0:dcf3c92487ca	1140	/* Write the Ethernet MAC-Addresses */
idinor	0:dcf3c92487ca	1141	#if LWIP_AUTOIP
idinor	0:dcf3c92487ca	1142	ETHADDR16_COPY(&ethhdr->dest, ethdst_hwaddr);
idinor	0:dcf3c92487ca	1143	#else /* LWIP_AUTOIP */
idinor	0:dcf3c92487ca	1144	ETHADDR16_COPY(&ethhdr->dest, ethdst_addr);
idinor	0:dcf3c92487ca	1145	#endif /* LWIP_AUTOIP */
idinor	0:dcf3c92487ca	1146	ETHADDR16_COPY(&ethhdr->src, ethsrc_addr);
idinor	0:dcf3c92487ca	1147	/* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
idinor	0:dcf3c92487ca	1148	* structure packing. */
idinor	0:dcf3c92487ca	1149	IPADDR2_COPY(&hdr->sipaddr, ipsrc_addr);
idinor	0:dcf3c92487ca	1150	IPADDR2_COPY(&hdr->dipaddr, ipdst_addr);
idinor	0:dcf3c92487ca	1151
idinor	0:dcf3c92487ca	1152	hdr->hwtype = PP_HTONS(HWTYPE_ETHERNET);
idinor	0:dcf3c92487ca	1153	hdr->proto = PP_HTONS(ETHTYPE_IP);
idinor	0:dcf3c92487ca	1154	/* set hwlen and protolen */
idinor	0:dcf3c92487ca	1155	hdr->hwlen = ETHARP_HWADDR_LEN;
idinor	0:dcf3c92487ca	1156	hdr->protolen = sizeof(ip_addr_t);
idinor	0:dcf3c92487ca	1157
idinor	0:dcf3c92487ca	1158	ethhdr->type = PP_HTONS(ETHTYPE_ARP);
idinor	0:dcf3c92487ca	1159	/* send ARP query */
idinor	0:dcf3c92487ca	1160	result = netif->linkoutput(netif, p);
idinor	0:dcf3c92487ca	1161	ETHARP_STATS_INC(etharp.xmit);
idinor	0:dcf3c92487ca	1162	/* free ARP query packet */
idinor	0:dcf3c92487ca	1163	pbuf_free(p);
idinor	0:dcf3c92487ca	1164	p = NULL;
idinor	0:dcf3c92487ca	1165	/* could not allocate pbuf for ARP request */
idinor	0:dcf3c92487ca	1166
idinor	0:dcf3c92487ca	1167	return result;
idinor	0:dcf3c92487ca	1168	}
idinor	0:dcf3c92487ca	1169
idinor	0:dcf3c92487ca	1170	/**
idinor	0:dcf3c92487ca	1171	* Send an ARP request packet asking for ipaddr.
idinor	0:dcf3c92487ca	1172	*
idinor	0:dcf3c92487ca	1173	* @param netif the lwip network interface on which to send the request
idinor	0:dcf3c92487ca	1174	* @param ipaddr the IP address for which to ask
idinor	0:dcf3c92487ca	1175	* @return ERR_OK if the request has been sent
idinor	0:dcf3c92487ca	1176	* ERR_MEM if the ARP packet couldn't be allocated
idinor	0:dcf3c92487ca	1177	* any other err_t on failure
idinor	0:dcf3c92487ca	1178	*/
idinor	0:dcf3c92487ca	1179	err_t
idinor	0:dcf3c92487ca	1180	etharp_request(struct netif netif, ip_addr_t ipaddr)
idinor	0:dcf3c92487ca	1181	{
idinor	0:dcf3c92487ca	1182	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_request: sending ARP request.\n"));
idinor	0:dcf3c92487ca	1183	return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, &ethbroadcast,
idinor	0:dcf3c92487ca	1184	(struct eth_addr *)netif->hwaddr, &netif->ip_addr, &ethzero,
idinor	0:dcf3c92487ca	1185	ipaddr, ARP_REQUEST);
idinor	0:dcf3c92487ca	1186	}
idinor	0:dcf3c92487ca	1187	#endif /* LWIP_ARP */
idinor	0:dcf3c92487ca	1188
idinor	0:dcf3c92487ca	1189	/**
idinor	0:dcf3c92487ca	1190	* Process received ethernet frames. Using this function instead of directly
idinor	0:dcf3c92487ca	1191	* calling ip_input and passing ARP frames through etharp in ethernetif_input,
idinor	0:dcf3c92487ca	1192	* the ARP cache is protected from concurrent access.
idinor	0:dcf3c92487ca	1193	*
idinor	0:dcf3c92487ca	1194	* @param p the recevied packet, p->payload pointing to the ethernet header
idinor	0:dcf3c92487ca	1195	* @param netif the network interface on which the packet was received
idinor	0:dcf3c92487ca	1196	*/
idinor	0:dcf3c92487ca	1197	err_t
idinor	0:dcf3c92487ca	1198	ethernet_input(struct pbuf p, struct netif netif)
idinor	0:dcf3c92487ca	1199	{
idinor	0:dcf3c92487ca	1200	struct eth_hdr* ethhdr;
idinor	0:dcf3c92487ca	1201	u16_t type;
idinor	0:dcf3c92487ca	1202
idinor	0:dcf3c92487ca	1203	/* points to packet payload, which starts with an Ethernet header */
idinor	0:dcf3c92487ca	1204	ethhdr = (struct eth_hdr *)p->payload;
idinor	0:dcf3c92487ca	1205	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE,
idinor	0:dcf3c92487ca	1206	("ethernet_input: dest:%"X8_F":%"X8_F":%"X8_F":%"X8_F":%"X8_F":%"X8_F", src:%"X8_F":%"X8_F":%"X8_F":%"X8_F":%"X8_F":%"X8_F", type:%"X16_F"\n",
idinor	0:dcf3c92487ca	1207	(unsigned)ethhdr->dest.addr[0], (unsigned)ethhdr->dest.addr[1], (unsigned)ethhdr->dest.addr[2],
idinor	0:dcf3c92487ca	1208	(unsigned)ethhdr->dest.addr[3], (unsigned)ethhdr->dest.addr[4], (unsigned)ethhdr->dest.addr[5],
idinor	0:dcf3c92487ca	1209	(unsigned)ethhdr->src.addr[0], (unsigned)ethhdr->src.addr[1], (unsigned)ethhdr->src.addr[2],
idinor	0:dcf3c92487ca	1210	(unsigned)ethhdr->src.addr[3], (unsigned)ethhdr->src.addr[4], (unsigned)ethhdr->src.addr[5],
idinor	0:dcf3c92487ca	1211	(unsigned)htons(ethhdr->type)));
idinor	0:dcf3c92487ca	1212
idinor	0:dcf3c92487ca	1213	type = ethhdr->type;
idinor	0:dcf3c92487ca	1214	#if ETHARP_SUPPORT_VLAN
idinor	0:dcf3c92487ca	1215	if (type == PP_HTONS(ETHTYPE_VLAN)) {
idinor	0:dcf3c92487ca	1216	struct eth_vlan_hdr vlan = (struct eth_vlan_hdr)(((char*)ethhdr) + SIZEOF_ETH_HDR);
idinor	0:dcf3c92487ca	1217	#ifdef ETHARP_VLAN_CHECK /* if not, allow all VLANs */
idinor	0:dcf3c92487ca	1218	if (VLAN_ID(vlan) != ETHARP_VLAN_CHECK) {
idinor	0:dcf3c92487ca	1219	/* silently ignore this packet: not for our VLAN */
idinor	0:dcf3c92487ca	1220	pbuf_free(p);
idinor	0:dcf3c92487ca	1221	return ERR_OK;
idinor	0:dcf3c92487ca	1222	}
idinor	0:dcf3c92487ca	1223	#endif /* ETHARP_VLAN_CHECK */
idinor	0:dcf3c92487ca	1224	type = vlan->tpid;
idinor	0:dcf3c92487ca	1225	}
idinor	0:dcf3c92487ca	1226	#endif /* ETHARP_SUPPORT_VLAN */
idinor	0:dcf3c92487ca	1227
idinor	0:dcf3c92487ca	1228	#if LWIP_ARP_FILTER_NETIF
idinor	0:dcf3c92487ca	1229	netif = LWIP_ARP_FILTER_NETIF_FN(p, netif, htons(type));
idinor	0:dcf3c92487ca	1230	#endif /* LWIP_ARP_FILTER_NETIF*/
idinor	0:dcf3c92487ca	1231
idinor	0:dcf3c92487ca	1232	switch (type) {
idinor	0:dcf3c92487ca	1233	#if LWIP_ARP
idinor	0:dcf3c92487ca	1234	/* IP packet? */
idinor	0:dcf3c92487ca	1235	case PP_HTONS(ETHTYPE_IP):
idinor	0:dcf3c92487ca	1236	if (!(netif->flags & NETIF_FLAG_ETHARP)) {
idinor	0:dcf3c92487ca	1237	goto free_and_return;
idinor	0:dcf3c92487ca	1238	}
idinor	0:dcf3c92487ca	1239	#if ETHARP_TRUST_IP_MAC
idinor	0:dcf3c92487ca	1240	/* update ARP table */
idinor	0:dcf3c92487ca	1241	etharp_ip_input(netif, p);
idinor	0:dcf3c92487ca	1242	#endif /* ETHARP_TRUST_IP_MAC */
idinor	0:dcf3c92487ca	1243	/* skip Ethernet header */
idinor	0:dcf3c92487ca	1244	if(pbuf_header(p, -(s16_t)SIZEOF_ETH_HDR)) {
idinor	0:dcf3c92487ca	1245	LWIP_ASSERT("Can't move over header in packet", 0);
idinor	0:dcf3c92487ca	1246	goto free_and_return;
idinor	0:dcf3c92487ca	1247	} else {
idinor	0:dcf3c92487ca	1248	/* pass to IP layer */
idinor	0:dcf3c92487ca	1249	ip_input(p, netif);
idinor	0:dcf3c92487ca	1250	}
idinor	0:dcf3c92487ca	1251	break;
idinor	0:dcf3c92487ca	1252
idinor	0:dcf3c92487ca	1253	case PP_HTONS(ETHTYPE_ARP):
idinor	0:dcf3c92487ca	1254	if (!(netif->flags & NETIF_FLAG_ETHARP)) {
idinor	0:dcf3c92487ca	1255	goto free_and_return;
idinor	0:dcf3c92487ca	1256	}
idinor	0:dcf3c92487ca	1257	/* pass p to ARP module */
idinor	0:dcf3c92487ca	1258	etharp_arp_input(netif, (struct eth_addr*)(netif->hwaddr), p);
idinor	0:dcf3c92487ca	1259	break;
idinor	0:dcf3c92487ca	1260	#endif /* LWIP_ARP */
idinor	0:dcf3c92487ca	1261	#if PPPOE_SUPPORT
idinor	0:dcf3c92487ca	1262	case PP_HTONS(ETHTYPE_PPPOEDISC): /* PPP Over Ethernet Discovery Stage */
idinor	0:dcf3c92487ca	1263	pppoe_disc_input(netif, p);
idinor	0:dcf3c92487ca	1264	break;
idinor	0:dcf3c92487ca	1265
idinor	0:dcf3c92487ca	1266	case PP_HTONS(ETHTYPE_PPPOE): /* PPP Over Ethernet Session Stage */
idinor	0:dcf3c92487ca	1267	pppoe_data_input(netif, p);
idinor	0:dcf3c92487ca	1268	break;
idinor	0:dcf3c92487ca	1269	#endif /* PPPOE_SUPPORT */
idinor	0:dcf3c92487ca	1270
idinor	0:dcf3c92487ca	1271	default:
idinor	0:dcf3c92487ca	1272	ETHARP_STATS_INC(etharp.proterr);
idinor	0:dcf3c92487ca	1273	ETHARP_STATS_INC(etharp.drop);
idinor	0:dcf3c92487ca	1274	goto free_and_return;
idinor	0:dcf3c92487ca	1275	}
idinor	0:dcf3c92487ca	1276
idinor	0:dcf3c92487ca	1277	/* This means the pbuf is freed or consumed,
idinor	0:dcf3c92487ca	1278	so the caller doesn't have to free it again */
idinor	0:dcf3c92487ca	1279	return ERR_OK;
idinor	0:dcf3c92487ca	1280
idinor	0:dcf3c92487ca	1281	free_and_return:
idinor	0:dcf3c92487ca	1282	pbuf_free(p);
idinor	0:dcf3c92487ca	1283	return ERR_OK;
idinor	0:dcf3c92487ca	1284	}
idinor	0:dcf3c92487ca	1285	#endif /* LWIP_ARP \|\| LWIP_ETHERNET */

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Type:	Library
Created:	20 Jul 2011
Imports:	35
Forks:	0
Commits:	1
Dependents:	1
Dependencies:	0
Followers:	1

lwip/netif/etharp.c@0:dcf3c92487ca, 2011-07-20 (annotated)

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