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lwip/netif/etharp.c@3:0c324737064d, 2010-11-09 (annotated)

Committer:: mbed714
Date:: Tue Nov 09 19:32:44 2010 +0000
Revision:: 3:0c324737064d
Parent:: 0:98aadd37a5c5

Who changed what in which revision?

User	Revision	Line number	New contents of line
mbed714	0:98aadd37a5c5	1	/**
mbed714	0:98aadd37a5c5	2	* @file
mbed714	0:98aadd37a5c5	3	* Address Resolution Protocol module for IP over Ethernet
mbed714	0:98aadd37a5c5	4	*
mbed714	0:98aadd37a5c5	5	* Functionally, ARP is divided into two parts. The first maps an IP address
mbed714	0:98aadd37a5c5	6	* to a physical address when sending a packet, and the second part answers
mbed714	0:98aadd37a5c5	7	* requests from other machines for our physical address.
mbed714	0:98aadd37a5c5	8	*
mbed714	0:98aadd37a5c5	9	* This implementation complies with RFC 826 (Ethernet ARP). It supports
mbed714	0:98aadd37a5c5	10	* Gratuitious ARP from RFC3220 (IP Mobility Support for IPv4) section 4.6
mbed714	0:98aadd37a5c5	11	* if an interface calls etharp_gratuitous(our_netif) upon address change.
mbed714	0:98aadd37a5c5	12	*/
mbed714	0:98aadd37a5c5	13
mbed714	0:98aadd37a5c5	14	/*
mbed714	0:98aadd37a5c5	15	* Copyright (c) 2001-2003 Swedish Institute of Computer Science.
mbed714	0:98aadd37a5c5	16	* Copyright (c) 2003-2004 Leon Woestenberg <leon.woestenberg@axon.tv>
mbed714	0:98aadd37a5c5	17	* Copyright (c) 2003-2004 Axon Digital Design B.V., The Netherlands.
mbed714	0:98aadd37a5c5	18	* All rights reserved.
mbed714	0:98aadd37a5c5	19	*
mbed714	0:98aadd37a5c5	20	* Redistribution and use in source and binary forms, with or without modification,
mbed714	0:98aadd37a5c5	21	* are permitted provided that the following conditions are met:
mbed714	0:98aadd37a5c5	22	*
mbed714	0:98aadd37a5c5	23	* 1. Redistributions of source code must retain the above copyright notice,
mbed714	0:98aadd37a5c5	24	* this list of conditions and the following disclaimer.
mbed714	0:98aadd37a5c5	25	* 2. Redistributions in binary form must reproduce the above copyright notice,
mbed714	0:98aadd37a5c5	26	* this list of conditions and the following disclaimer in the documentation
mbed714	0:98aadd37a5c5	27	* and/or other materials provided with the distribution.
mbed714	0:98aadd37a5c5	28	* 3. The name of the author may not be used to endorse or promote products
mbed714	0:98aadd37a5c5	29	* derived from this software without specific prior written permission.
mbed714	0:98aadd37a5c5	30	*
mbed714	0:98aadd37a5c5	31	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
mbed714	0:98aadd37a5c5	32	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
mbed714	0:98aadd37a5c5	33	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
mbed714	0:98aadd37a5c5	34	* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
mbed714	0:98aadd37a5c5	35	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
mbed714	0:98aadd37a5c5	36	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
mbed714	0:98aadd37a5c5	37	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
mbed714	0:98aadd37a5c5	38	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
mbed714	0:98aadd37a5c5	39	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
mbed714	0:98aadd37a5c5	40	* OF SUCH DAMAGE.
mbed714	0:98aadd37a5c5	41	*
mbed714	0:98aadd37a5c5	42	* This file is part of the lwIP TCP/IP stack.
mbed714	0:98aadd37a5c5	43	*
mbed714	0:98aadd37a5c5	44	*/
mbed714	0:98aadd37a5c5	45
mbed714	0:98aadd37a5c5	46	#include "lwip/opt.h"
mbed714	0:98aadd37a5c5	47
mbed714	0:98aadd37a5c5	48	#if LWIP_ARP \|\| LWIP_ETHERNET
mbed714	0:98aadd37a5c5	49
mbed714	0:98aadd37a5c5	50	#include "lwip/ip_addr.h"
mbed714	0:98aadd37a5c5	51	#include "lwip/def.h"
mbed714	0:98aadd37a5c5	52	#include "lwip/ip.h"
mbed714	0:98aadd37a5c5	53	#include "lwip/stats.h"
mbed714	0:98aadd37a5c5	54	#include "lwip/snmp.h"
mbed714	0:98aadd37a5c5	55	#include "lwip/dhcp.h"
mbed714	0:98aadd37a5c5	56	#include "lwip/autoip.h"
mbed714	0:98aadd37a5c5	57	#include "netif/etharp.h"
mbed714	0:98aadd37a5c5	58
mbed714	0:98aadd37a5c5	59	#if PPPOE_SUPPORT
mbed714	0:98aadd37a5c5	60	#include "netif/ppp_oe.h"
mbed714	0:98aadd37a5c5	61	#endif /* PPPOE_SUPPORT */
mbed714	0:98aadd37a5c5	62
mbed714	0:98aadd37a5c5	63	#include <string.h>
mbed714	0:98aadd37a5c5	64
mbed714	0:98aadd37a5c5	65	const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}};
mbed714	0:98aadd37a5c5	66	const struct eth_addr ethzero = {{0,0,0,0,0,0}};
mbed714	0:98aadd37a5c5	67
mbed714	0:98aadd37a5c5	68	#if LWIP_ARP /* don't build if not configured for use in lwipopts.h */
mbed714	0:98aadd37a5c5	69
mbed714	0:98aadd37a5c5	70	/** the time an ARP entry stays valid after its last update,
mbed714	0:98aadd37a5c5	71	* for ARP_TMR_INTERVAL = 5000, this is
mbed714	0:98aadd37a5c5	72	* (240 * 5) seconds = 20 minutes.
mbed714	0:98aadd37a5c5	73	*/
mbed714	0:98aadd37a5c5	74	#define ARP_MAXAGE 240
mbed714	0:98aadd37a5c5	75	/** the time an ARP entry stays pending after first request,
mbed714	0:98aadd37a5c5	76	* for ARP_TMR_INTERVAL = 5000, this is
mbed714	0:98aadd37a5c5	77	* (2 * 5) seconds = 10 seconds.
mbed714	0:98aadd37a5c5	78	*
mbed714	0:98aadd37a5c5	79	* @internal Keep this number at least 2, otherwise it might
mbed714	0:98aadd37a5c5	80	* run out instantly if the timeout occurs directly after a request.
mbed714	0:98aadd37a5c5	81	*/
mbed714	0:98aadd37a5c5	82	#define ARP_MAXPENDING 2
mbed714	0:98aadd37a5c5	83
mbed714	0:98aadd37a5c5	84	#define HWTYPE_ETHERNET 1
mbed714	0:98aadd37a5c5	85
mbed714	0:98aadd37a5c5	86	enum etharp_state {
mbed714	0:98aadd37a5c5	87	ETHARP_STATE_EMPTY = 0,
mbed714	0:98aadd37a5c5	88	ETHARP_STATE_PENDING,
mbed714	0:98aadd37a5c5	89	ETHARP_STATE_STABLE
mbed714	0:98aadd37a5c5	90	};
mbed714	0:98aadd37a5c5	91
mbed714	0:98aadd37a5c5	92	struct etharp_entry {
mbed714	0:98aadd37a5c5	93	#if ARP_QUEUEING
mbed714	0:98aadd37a5c5	94	/** Pointer to queue of pending outgoing packets on this ARP entry. */
mbed714	0:98aadd37a5c5	95	struct etharp_q_entry *q;
mbed714	0:98aadd37a5c5	96	#endif /* ARP_QUEUEING */
mbed714	0:98aadd37a5c5	97	ip_addr_t ipaddr;
mbed714	0:98aadd37a5c5	98	struct eth_addr ethaddr;
mbed714	0:98aadd37a5c5	99	#if LWIP_SNMP
mbed714	0:98aadd37a5c5	100	struct netif *netif;
mbed714	0:98aadd37a5c5	101	#endif /* LWIP_SNMP */
mbed714	0:98aadd37a5c5	102	u8_t state;
mbed714	0:98aadd37a5c5	103	u8_t ctime;
mbed714	0:98aadd37a5c5	104	#if ETHARP_SUPPORT_STATIC_ENTRIES
mbed714	0:98aadd37a5c5	105	u8_t static_entry;
mbed714	0:98aadd37a5c5	106	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
mbed714	0:98aadd37a5c5	107	};
mbed714	0:98aadd37a5c5	108
mbed714	0:98aadd37a5c5	109	static struct etharp_entry arp_table[ARP_TABLE_SIZE];
mbed714	0:98aadd37a5c5	110
mbed714	0:98aadd37a5c5	111	#if !LWIP_NETIF_HWADDRHINT
mbed714	0:98aadd37a5c5	112	static u8_t etharp_cached_entry;
mbed714	0:98aadd37a5c5	113	#endif /* !LWIP_NETIF_HWADDRHINT */
mbed714	0:98aadd37a5c5	114
mbed714	0:98aadd37a5c5	115	/** Try hard to create a new entry - we want the IP address to appear in
mbed714	0:98aadd37a5c5	116	the cache (even if this means removing an active entry or so). */
mbed714	0:98aadd37a5c5	117	#define ETHARP_FLAG_TRY_HARD 1
mbed714	0:98aadd37a5c5	118	#define ETHARP_FLAG_FIND_ONLY 2
mbed714	0:98aadd37a5c5	119	#define ETHARP_FLAG_STATIC_ENTRY 4
mbed714	0:98aadd37a5c5	120
mbed714	0:98aadd37a5c5	121	#if LWIP_NETIF_HWADDRHINT
mbed714	0:98aadd37a5c5	122	#define ETHARP_SET_HINT(netif, hint) if (((netif) != NULL) && ((netif)->addr_hint != NULL)) \
mbed714	0:98aadd37a5c5	123	*((netif)->addr_hint) = (hint);
mbed714	0:98aadd37a5c5	124	#else /* LWIP_NETIF_HWADDRHINT */
mbed714	0:98aadd37a5c5	125	#define ETHARP_SET_HINT(netif, hint) (etharp_cached_entry = (hint))
mbed714	0:98aadd37a5c5	126	#endif /* LWIP_NETIF_HWADDRHINT */
mbed714	0:98aadd37a5c5	127
mbed714	0:98aadd37a5c5	128	static err_t update_arp_entry(struct netif netif, ip_addr_t ipaddr, struct eth_addr *ethaddr, u8_t flags);
mbed714	0:98aadd37a5c5	129
mbed714	0:98aadd37a5c5	130
mbed714	0:98aadd37a5c5	131	/* Some checks, instead of etharp_init(): */
mbed714	0:98aadd37a5c5	132	#if (LWIP_ARP && (ARP_TABLE_SIZE > 0x7f))
mbed714	0:98aadd37a5c5	133	#error "ARP_TABLE_SIZE must fit in an s8_t, you have to reduce it in your lwipopts.h"
mbed714	0:98aadd37a5c5	134	#endif
mbed714	0:98aadd37a5c5	135
mbed714	0:98aadd37a5c5	136
mbed714	0:98aadd37a5c5	137	#if ARP_QUEUEING
mbed714	0:98aadd37a5c5	138	/**
mbed714	0:98aadd37a5c5	139	* Free a complete queue of etharp entries
mbed714	0:98aadd37a5c5	140	*
mbed714	0:98aadd37a5c5	141	* @param q a qeueue of etharp_q_entry's to free
mbed714	0:98aadd37a5c5	142	*/
mbed714	0:98aadd37a5c5	143	static void
mbed714	0:98aadd37a5c5	144	free_etharp_q(struct etharp_q_entry *q)
mbed714	0:98aadd37a5c5	145	{
mbed714	0:98aadd37a5c5	146	struct etharp_q_entry *r;
mbed714	0:98aadd37a5c5	147	LWIP_ASSERT("q != NULL", q != NULL);
mbed714	0:98aadd37a5c5	148	LWIP_ASSERT("q->p != NULL", q->p != NULL);
mbed714	0:98aadd37a5c5	149	while (q) {
mbed714	0:98aadd37a5c5	150	r = q;
mbed714	0:98aadd37a5c5	151	q = q->next;
mbed714	0:98aadd37a5c5	152	LWIP_ASSERT("r->p != NULL", (r->p != NULL));
mbed714	0:98aadd37a5c5	153	pbuf_free(r->p);
mbed714	0:98aadd37a5c5	154	memp_free(MEMP_ARP_QUEUE, r);
mbed714	0:98aadd37a5c5	155	}
mbed714	0:98aadd37a5c5	156	}
mbed714	0:98aadd37a5c5	157	#endif /* ARP_QUEUEING */
mbed714	0:98aadd37a5c5	158
mbed714	0:98aadd37a5c5	159	/** Clean up ARP table entries */
mbed714	0:98aadd37a5c5	160	static void
mbed714	0:98aadd37a5c5	161	free_entry(int i)
mbed714	0:98aadd37a5c5	162	{
mbed714	0:98aadd37a5c5	163	/* remove from SNMP ARP index tree */
mbed714	0:98aadd37a5c5	164	snmp_delete_arpidx_tree(arp_table[i].netif, &arp_table[i].ipaddr);
mbed714	0:98aadd37a5c5	165	#if ARP_QUEUEING
mbed714	0:98aadd37a5c5	166	/* and empty packet queue */
mbed714	0:98aadd37a5c5	167	if (arp_table[i].q != NULL) {
mbed714	0:98aadd37a5c5	168	/* remove all queued packets */
mbed714	0:98aadd37a5c5	169	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: freeing entry %"U16_F", packet queue %p.\n", (u16_t)i, (void *)(arp_table[i].q)));
mbed714	0:98aadd37a5c5	170	free_etharp_q(arp_table[i].q);
mbed714	0:98aadd37a5c5	171	arp_table[i].q = NULL;
mbed714	0:98aadd37a5c5	172	}
mbed714	0:98aadd37a5c5	173	#endif /* ARP_QUEUEING */
mbed714	0:98aadd37a5c5	174	/* recycle entry for re-use */
mbed714	0:98aadd37a5c5	175	arp_table[i].state = ETHARP_STATE_EMPTY;
mbed714	0:98aadd37a5c5	176	#if ETHARP_SUPPORT_STATIC_ENTRIES
mbed714	0:98aadd37a5c5	177	arp_table[i].static_entry = 0;
mbed714	0:98aadd37a5c5	178	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
mbed714	0:98aadd37a5c5	179	#ifdef LWIP_DEBUG
mbed714	0:98aadd37a5c5	180	/* for debugging, clean out the complete entry */
mbed714	0:98aadd37a5c5	181	arp_table[i].ctime = 0;
mbed714	0:98aadd37a5c5	182	#if LWIP_SNMP
mbed714	0:98aadd37a5c5	183	arp_table[i].netif = NULL;
mbed714	0:98aadd37a5c5	184	#endif /* LWIP_SNMP */
mbed714	0:98aadd37a5c5	185	ip_addr_set_zero(&arp_table[i].ipaddr);
mbed714	0:98aadd37a5c5	186	arp_table[i].ethaddr = ethzero;
mbed714	0:98aadd37a5c5	187	#endif /* LWIP_DEBUG */
mbed714	0:98aadd37a5c5	188	}
mbed714	0:98aadd37a5c5	189
mbed714	0:98aadd37a5c5	190	/**
mbed714	0:98aadd37a5c5	191	* Clears expired entries in the ARP table.
mbed714	0:98aadd37a5c5	192	*
mbed714	0:98aadd37a5c5	193	* This function should be called every ETHARP_TMR_INTERVAL milliseconds (5 seconds),
mbed714	0:98aadd37a5c5	194	* in order to expire entries in the ARP table.
mbed714	0:98aadd37a5c5	195	*/
mbed714	0:98aadd37a5c5	196	void
mbed714	0:98aadd37a5c5	197	etharp_tmr(void)
mbed714	0:98aadd37a5c5	198	{
mbed714	0:98aadd37a5c5	199	u8_t i;
mbed714	0:98aadd37a5c5	200
mbed714	0:98aadd37a5c5	201	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer\n"));
mbed714	0:98aadd37a5c5	202	/* remove expired entries from the ARP table */
mbed714	0:98aadd37a5c5	203	for (i = 0; i < ARP_TABLE_SIZE; ++i) {
mbed714	0:98aadd37a5c5	204	u8_t state = arp_table[i].state;
mbed714	0:98aadd37a5c5	205	if (state != ETHARP_STATE_EMPTY
mbed714	0:98aadd37a5c5	206	#if ETHARP_SUPPORT_STATIC_ENTRIES
mbed714	0:98aadd37a5c5	207	&& (arp_table[i].static_entry == 0)
mbed714	0:98aadd37a5c5	208	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
mbed714	0:98aadd37a5c5	209	) {
mbed714	0:98aadd37a5c5	210	arp_table[i].ctime++;
mbed714	0:98aadd37a5c5	211	if ((arp_table[i].ctime >= ARP_MAXAGE) \|\|
mbed714	0:98aadd37a5c5	212	((arp_table[i].state == ETHARP_STATE_PENDING) &&
mbed714	0:98aadd37a5c5	213	(arp_table[i].ctime >= ARP_MAXPENDING))) {
mbed714	0:98aadd37a5c5	214	/* pending or stable entry has become old! */
mbed714	0:98aadd37a5c5	215	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: expired %s entry %"U16_F".\n",
mbed714	0:98aadd37a5c5	216	arp_table[i].state == ETHARP_STATE_STABLE ? "stable" : "pending", (u16_t)i));
mbed714	0:98aadd37a5c5	217	/* clean up entries that have just been expired */
mbed714	0:98aadd37a5c5	218	free_entry(i);
mbed714	0:98aadd37a5c5	219	}
mbed714	0:98aadd37a5c5	220	#if ARP_QUEUEING
mbed714	0:98aadd37a5c5	221	/* still pending entry? (not expired) */
mbed714	0:98aadd37a5c5	222	if (arp_table[i].state == ETHARP_STATE_PENDING) {
mbed714	0:98aadd37a5c5	223	/* resend an ARP query here? */
mbed714	0:98aadd37a5c5	224	}
mbed714	0:98aadd37a5c5	225	#endif /* ARP_QUEUEING */
mbed714	0:98aadd37a5c5	226	}
mbed714	0:98aadd37a5c5	227	}
mbed714	0:98aadd37a5c5	228	}
mbed714	0:98aadd37a5c5	229
mbed714	0:98aadd37a5c5	230	/**
mbed714	0:98aadd37a5c5	231	* Search the ARP table for a matching or new entry.
mbed714	0:98aadd37a5c5	232	*
mbed714	0:98aadd37a5c5	233	* If an IP address is given, return a pending or stable ARP entry that matches
mbed714	0:98aadd37a5c5	234	* the address. If no match is found, create a new entry with this address set,
mbed714	0:98aadd37a5c5	235	* but in state ETHARP_EMPTY. The caller must check and possibly change the
mbed714	0:98aadd37a5c5	236	* state of the returned entry.
mbed714	0:98aadd37a5c5	237	*
mbed714	0:98aadd37a5c5	238	* If ipaddr is NULL, return a initialized new entry in state ETHARP_EMPTY.
mbed714	0:98aadd37a5c5	239	*
mbed714	0:98aadd37a5c5	240	* In all cases, attempt to create new entries from an empty entry. If no
mbed714	0:98aadd37a5c5	241	* empty entries are available and ETHARP_FLAG_TRY_HARD flag is set, recycle
mbed714	0:98aadd37a5c5	242	* old entries. Heuristic choose the least important entry for recycling.
mbed714	0:98aadd37a5c5	243	*
mbed714	0:98aadd37a5c5	244	* @param ipaddr IP address to find in ARP cache, or to add if not found.
mbed714	0:98aadd37a5c5	245	* @param flags @see definition of ETHARP_FLAG_*
mbed714	0:98aadd37a5c5	246	* @param netif netif related to this address (used for NETIF_HWADDRHINT)
mbed714	0:98aadd37a5c5	247	*
mbed714	0:98aadd37a5c5	248	* @return The ARP entry index that matched or is created, ERR_MEM if no
mbed714	0:98aadd37a5c5	249	* entry is found or could be recycled.
mbed714	0:98aadd37a5c5	250	*/
mbed714	0:98aadd37a5c5	251	static s8_t
mbed714	0:98aadd37a5c5	252	find_entry(ip_addr_t *ipaddr, u8_t flags)
mbed714	0:98aadd37a5c5	253	{
mbed714	0:98aadd37a5c5	254	s8_t old_pending = ARP_TABLE_SIZE, old_stable = ARP_TABLE_SIZE;
mbed714	0:98aadd37a5c5	255	s8_t empty = ARP_TABLE_SIZE;
mbed714	0:98aadd37a5c5	256	u8_t i = 0, age_pending = 0, age_stable = 0;
mbed714	0:98aadd37a5c5	257	#if ARP_QUEUEING
mbed714	0:98aadd37a5c5	258	/* oldest entry with packets on queue */
mbed714	0:98aadd37a5c5	259	s8_t old_queue = ARP_TABLE_SIZE;
mbed714	0:98aadd37a5c5	260	/* its age */
mbed714	0:98aadd37a5c5	261	u8_t age_queue = 0;
mbed714	0:98aadd37a5c5	262	#endif /* ARP_QUEUEING */
mbed714	0:98aadd37a5c5	263
mbed714	0:98aadd37a5c5	264	/**
mbed714	0:98aadd37a5c5	265	* a) do a search through the cache, remember candidates
mbed714	0:98aadd37a5c5	266	* b) select candidate entry
mbed714	0:98aadd37a5c5	267	* c) create new entry
mbed714	0:98aadd37a5c5	268	*/
mbed714	0:98aadd37a5c5	269
mbed714	0:98aadd37a5c5	270	/* a) in a single search sweep, do all of this
mbed714	0:98aadd37a5c5	271	* 1) remember the first empty entry (if any)
mbed714	0:98aadd37a5c5	272	* 2) remember the oldest stable entry (if any)
mbed714	0:98aadd37a5c5	273	* 3) remember the oldest pending entry without queued packets (if any)
mbed714	0:98aadd37a5c5	274	* 4) remember the oldest pending entry with queued packets (if any)
mbed714	0:98aadd37a5c5	275	* 5) search for a matching IP entry, either pending or stable
mbed714	0:98aadd37a5c5	276	* until 5 matches, or all entries are searched for.
mbed714	0:98aadd37a5c5	277	*/
mbed714	0:98aadd37a5c5	278
mbed714	0:98aadd37a5c5	279	for (i = 0; i < ARP_TABLE_SIZE; ++i) {
mbed714	0:98aadd37a5c5	280	u8_t state = arp_table[i].state;
mbed714	0:98aadd37a5c5	281	/* no empty entry found yet and now we do find one? */
mbed714	0:98aadd37a5c5	282	if ((empty == ARP_TABLE_SIZE) && (state == ETHARP_STATE_EMPTY)) {
mbed714	0:98aadd37a5c5	283	LWIP_DEBUGF(ETHARP_DEBUG, ("find_entry: found empty entry %"U16_F"\n", (u16_t)i));
mbed714	0:98aadd37a5c5	284	/* remember first empty entry */
mbed714	0:98aadd37a5c5	285	empty = i;
mbed714	0:98aadd37a5c5	286	} else if (state != ETHARP_STATE_EMPTY) {
mbed714	0:98aadd37a5c5	287	LWIP_ASSERT("state == ETHARP_STATE_PENDING \|\| state == ETHARP_STATE_STABLE",
mbed714	0:98aadd37a5c5	288	state == ETHARP_STATE_PENDING \|\| state == ETHARP_STATE_STABLE);
mbed714	0:98aadd37a5c5	289	/* if given, does IP address match IP address in ARP entry? */
mbed714	0:98aadd37a5c5	290	if (ipaddr && ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
mbed714	0:98aadd37a5c5	291	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: found matching entry %"U16_F"\n", (u16_t)i));
mbed714	0:98aadd37a5c5	292	/* found exact IP address match, simply bail out */
mbed714	0:98aadd37a5c5	293	return i;
mbed714	0:98aadd37a5c5	294	}
mbed714	0:98aadd37a5c5	295	/* pending entry? */
mbed714	0:98aadd37a5c5	296	if (state == ETHARP_STATE_PENDING) {
mbed714	0:98aadd37a5c5	297	/* pending with queued packets? */
mbed714	0:98aadd37a5c5	298	#if ARP_QUEUEING
mbed714	0:98aadd37a5c5	299	if (arp_table[i].q != NULL) {
mbed714	0:98aadd37a5c5	300	if (arp_table[i].ctime >= age_queue) {
mbed714	0:98aadd37a5c5	301	old_queue = i;
mbed714	0:98aadd37a5c5	302	age_queue = arp_table[i].ctime;
mbed714	0:98aadd37a5c5	303	}
mbed714	0:98aadd37a5c5	304	} else
mbed714	0:98aadd37a5c5	305	#endif /* ARP_QUEUEING */
mbed714	0:98aadd37a5c5	306	/* pending without queued packets? */
mbed714	0:98aadd37a5c5	307	{
mbed714	0:98aadd37a5c5	308	if (arp_table[i].ctime >= age_pending) {
mbed714	0:98aadd37a5c5	309	old_pending = i;
mbed714	0:98aadd37a5c5	310	age_pending = arp_table[i].ctime;
mbed714	0:98aadd37a5c5	311	}
mbed714	0:98aadd37a5c5	312	}
mbed714	0:98aadd37a5c5	313	/* stable entry? */
mbed714	0:98aadd37a5c5	314	} else if (state == ETHARP_STATE_STABLE) {
mbed714	0:98aadd37a5c5	315	#if ETHARP_SUPPORT_STATIC_ENTRIES
mbed714	0:98aadd37a5c5	316	/* don't record old_stable for static entries since they never expire */
mbed714	0:98aadd37a5c5	317	if (arp_table[i].static_entry == 0)
mbed714	0:98aadd37a5c5	318	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
mbed714	0:98aadd37a5c5	319	{
mbed714	0:98aadd37a5c5	320	/* remember entry with oldest stable entry in oldest, its age in maxtime */
mbed714	0:98aadd37a5c5	321	if (arp_table[i].ctime >= age_stable) {
mbed714	0:98aadd37a5c5	322	old_stable = i;
mbed714	0:98aadd37a5c5	323	age_stable = arp_table[i].ctime;
mbed714	0:98aadd37a5c5	324	}
mbed714	0:98aadd37a5c5	325	}
mbed714	0:98aadd37a5c5	326	}
mbed714	0:98aadd37a5c5	327	}
mbed714	0:98aadd37a5c5	328	}
mbed714	0:98aadd37a5c5	329	/* { we have no match } => try to create a new entry */
mbed714	0:98aadd37a5c5	330
mbed714	0:98aadd37a5c5	331	/* don't create new entry, only search? */
mbed714	0:98aadd37a5c5	332	if (((flags & ETHARP_FLAG_FIND_ONLY) != 0) \|\|
mbed714	0:98aadd37a5c5	333	/* or no empty entry found and not allowed to recycle? */
mbed714	0:98aadd37a5c5	334	((empty == ARP_TABLE_SIZE) && ((flags & ETHARP_FLAG_TRY_HARD) == 0))) {
mbed714	0:98aadd37a5c5	335	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: no empty entry found and not allowed to recycle\n"));
mbed714	0:98aadd37a5c5	336	return (s8_t)ERR_MEM;
mbed714	0:98aadd37a5c5	337	}
mbed714	0:98aadd37a5c5	338
mbed714	0:98aadd37a5c5	339	/* b) choose the least destructive entry to recycle:
mbed714	0:98aadd37a5c5	340	* 1) empty entry
mbed714	0:98aadd37a5c5	341	* 2) oldest stable entry
mbed714	0:98aadd37a5c5	342	* 3) oldest pending entry without queued packets
mbed714	0:98aadd37a5c5	343	* 4) oldest pending entry with queued packets
mbed714	0:98aadd37a5c5	344	*
mbed714	0:98aadd37a5c5	345	* { ETHARP_FLAG_TRY_HARD is set at this point }
mbed714	0:98aadd37a5c5	346	*/
mbed714	0:98aadd37a5c5	347
mbed714	0:98aadd37a5c5	348	/* 1) empty entry available? */
mbed714	0:98aadd37a5c5	349	if (empty < ARP_TABLE_SIZE) {
mbed714	0:98aadd37a5c5	350	i = empty;
mbed714	0:98aadd37a5c5	351	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting empty entry %"U16_F"\n", (u16_t)i));
mbed714	0:98aadd37a5c5	352	} else {
mbed714	0:98aadd37a5c5	353	/* 2) found recyclable stable entry? */
mbed714	0:98aadd37a5c5	354	if (old_stable < ARP_TABLE_SIZE) {
mbed714	0:98aadd37a5c5	355	/* recycle oldest stable*/
mbed714	0:98aadd37a5c5	356	i = old_stable;
mbed714	0:98aadd37a5c5	357	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest stable entry %"U16_F"\n", (u16_t)i));
mbed714	0:98aadd37a5c5	358	#if ARP_QUEUEING
mbed714	0:98aadd37a5c5	359	/* no queued packets should exist on stable entries */
mbed714	0:98aadd37a5c5	360	LWIP_ASSERT("arp_table[i].q == NULL", arp_table[i].q == NULL);
mbed714	0:98aadd37a5c5	361	#endif /* ARP_QUEUEING */
mbed714	0:98aadd37a5c5	362	/* 3) found recyclable pending entry without queued packets? */
mbed714	0:98aadd37a5c5	363	} else if (old_pending < ARP_TABLE_SIZE) {
mbed714	0:98aadd37a5c5	364	/* recycle oldest pending */
mbed714	0:98aadd37a5c5	365	i = old_pending;
mbed714	0:98aadd37a5c5	366	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest pending entry %"U16_F" (without queue)\n", (u16_t)i));
mbed714	0:98aadd37a5c5	367	#if ARP_QUEUEING
mbed714	0:98aadd37a5c5	368	/* 4) found recyclable pending entry with queued packets? */
mbed714	0:98aadd37a5c5	369	} else if (old_queue < ARP_TABLE_SIZE) {
mbed714	0:98aadd37a5c5	370	/* recycle oldest pending (queued packets are free in free_entry) */
mbed714	0:98aadd37a5c5	371	i = old_queue;
mbed714	0:98aadd37a5c5	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)));
mbed714	0:98aadd37a5c5	373	#endif /* ARP_QUEUEING */
mbed714	0:98aadd37a5c5	374	/* no empty or recyclable entries found */
mbed714	0:98aadd37a5c5	375	} else {
mbed714	0:98aadd37a5c5	376	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: no empty or recyclable entries found\n"));
mbed714	0:98aadd37a5c5	377	return (s8_t)ERR_MEM;
mbed714	0:98aadd37a5c5	378	}
mbed714	0:98aadd37a5c5	379
mbed714	0:98aadd37a5c5	380	/* { empty or recyclable entry found } */
mbed714	0:98aadd37a5c5	381	LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
mbed714	0:98aadd37a5c5	382	free_entry(i);
mbed714	0:98aadd37a5c5	383	}
mbed714	0:98aadd37a5c5	384
mbed714	0:98aadd37a5c5	385	LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
mbed714	0:98aadd37a5c5	386	LWIP_ASSERT("arp_table[i].state == ETHARP_STATE_EMPTY",
mbed714	0:98aadd37a5c5	387	arp_table[i].state == ETHARP_STATE_EMPTY);
mbed714	0:98aadd37a5c5	388
mbed714	0:98aadd37a5c5	389	/* IP address given? */
mbed714	0:98aadd37a5c5	390	if (ipaddr != NULL) {
mbed714	0:98aadd37a5c5	391	/* set IP address */
mbed714	0:98aadd37a5c5	392	ip_addr_copy(arp_table[i].ipaddr, *ipaddr);
mbed714	0:98aadd37a5c5	393	}
mbed714	0:98aadd37a5c5	394	arp_table[i].ctime = 0;
mbed714	0:98aadd37a5c5	395	#if ETHARP_SUPPORT_STATIC_ENTRIES
mbed714	0:98aadd37a5c5	396	arp_table[i].static_entry = 0;
mbed714	0:98aadd37a5c5	397	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
mbed714	0:98aadd37a5c5	398	return (err_t)i;
mbed714	0:98aadd37a5c5	399	}
mbed714	0:98aadd37a5c5	400
mbed714	0:98aadd37a5c5	401	/**
mbed714	0:98aadd37a5c5	402	* Send an IP packet on the network using netif->linkoutput
mbed714	0:98aadd37a5c5	403	* The ethernet header is filled in before sending.
mbed714	0:98aadd37a5c5	404	*
mbed714	0:98aadd37a5c5	405	* @params netif the lwIP network interface on which to send the packet
mbed714	0:98aadd37a5c5	406	* @params p the packet to send, p->payload pointing to the (uninitialized) ethernet header
mbed714	0:98aadd37a5c5	407	* @params src the source MAC address to be copied into the ethernet header
mbed714	0:98aadd37a5c5	408	* @params dst the destination MAC address to be copied into the ethernet header
mbed714	0:98aadd37a5c5	409	* @return ERR_OK if the packet was sent, any other err_t on failure
mbed714	0:98aadd37a5c5	410	*/
mbed714	0:98aadd37a5c5	411	static err_t
mbed714	0:98aadd37a5c5	412	etharp_send_ip(struct netif netif, struct pbuf p, struct eth_addr src, struct eth_addr dst)
mbed714	0:98aadd37a5c5	413	{
mbed714	0:98aadd37a5c5	414	struct eth_hdr ethhdr = (struct eth_hdr )p->payload;
mbed714	0:98aadd37a5c5	415
mbed714	0:98aadd37a5c5	416	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
mbed714	0:98aadd37a5c5	417	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
mbed714	0:98aadd37a5c5	418	ETHADDR32_COPY(&ethhdr->dest, dst);
mbed714	0:98aadd37a5c5	419	ETHADDR16_COPY(&ethhdr->src, src);
mbed714	0:98aadd37a5c5	420	ethhdr->type = PP_HTONS(ETHTYPE_IP);
mbed714	0:98aadd37a5c5	421	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_send_ip: sending packet %p\n", (void *)p));
mbed714	0:98aadd37a5c5	422	/* send the packet */
mbed714	0:98aadd37a5c5	423	return netif->linkoutput(netif, p);
mbed714	0:98aadd37a5c5	424	}
mbed714	0:98aadd37a5c5	425
mbed714	0:98aadd37a5c5	426	/**
mbed714	0:98aadd37a5c5	427	* Update (or insert) a IP/MAC address pair in the ARP cache.
mbed714	0:98aadd37a5c5	428	*
mbed714	0:98aadd37a5c5	429	* If a pending entry is resolved, any queued packets will be sent
mbed714	0:98aadd37a5c5	430	* at this point.
mbed714	0:98aadd37a5c5	431	*
mbed714	0:98aadd37a5c5	432	* @param netif netif related to this entry (used for NETIF_ADDRHINT)
mbed714	0:98aadd37a5c5	433	* @param ipaddr IP address of the inserted ARP entry.
mbed714	0:98aadd37a5c5	434	* @param ethaddr Ethernet address of the inserted ARP entry.
mbed714	0:98aadd37a5c5	435	* @param flags @see definition of ETHARP_FLAG_*
mbed714	0:98aadd37a5c5	436	*
mbed714	0:98aadd37a5c5	437	* @return
mbed714	0:98aadd37a5c5	438	* - ERR_OK Succesfully updated ARP cache.
mbed714	0:98aadd37a5c5	439	* - ERR_MEM If we could not add a new ARP entry when ETHARP_FLAG_TRY_HARD was set.
mbed714	0:98aadd37a5c5	440	* - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
mbed714	0:98aadd37a5c5	441	*
mbed714	0:98aadd37a5c5	442	* @see pbuf_free()
mbed714	0:98aadd37a5c5	443	*/
mbed714	0:98aadd37a5c5	444	static err_t
mbed714	0:98aadd37a5c5	445	update_arp_entry(struct netif netif, ip_addr_t ipaddr, struct eth_addr *ethaddr, u8_t flags)
mbed714	0:98aadd37a5c5	446	{
mbed714	0:98aadd37a5c5	447	s8_t i;
mbed714	0:98aadd37a5c5	448	LWIP_ASSERT("netif->hwaddr_len == ETHARP_HWADDR_LEN", netif->hwaddr_len == ETHARP_HWADDR_LEN);
mbed714	0:98aadd37a5c5	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",
mbed714	0:98aadd37a5c5	450	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
mbed714	0:98aadd37a5c5	451	ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
mbed714	0:98aadd37a5c5	452	ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
mbed714	0:98aadd37a5c5	453	/* non-unicast address? */
mbed714	0:98aadd37a5c5	454	if (ip_addr_isany(ipaddr) \|\|
mbed714	0:98aadd37a5c5	455	ip_addr_isbroadcast(ipaddr, netif) \|\|
mbed714	0:98aadd37a5c5	456	ip_addr_ismulticast(ipaddr)) {
mbed714	0:98aadd37a5c5	457	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: will not add non-unicast IP address to ARP cache\n"));
mbed714	0:98aadd37a5c5	458	return ERR_ARG;
mbed714	0:98aadd37a5c5	459	}
mbed714	0:98aadd37a5c5	460	/* find or create ARP entry */
mbed714	0:98aadd37a5c5	461	i = find_entry(ipaddr, flags);
mbed714	0:98aadd37a5c5	462	/* bail out if no entry could be found */
mbed714	0:98aadd37a5c5	463	if (i < 0) {
mbed714	0:98aadd37a5c5	464	return (err_t)i;
mbed714	0:98aadd37a5c5	465	}
mbed714	0:98aadd37a5c5	466
mbed714	0:98aadd37a5c5	467	#if ETHARP_SUPPORT_STATIC_ENTRIES
mbed714	0:98aadd37a5c5	468	if (flags & ETHARP_FLAG_STATIC_ENTRY) {
mbed714	0:98aadd37a5c5	469	/* record static type */
mbed714	0:98aadd37a5c5	470	arp_table[i].static_entry = 1;
mbed714	0:98aadd37a5c5	471	}
mbed714	0:98aadd37a5c5	472	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
mbed714	0:98aadd37a5c5	473
mbed714	0:98aadd37a5c5	474	/* mark it stable */
mbed714	0:98aadd37a5c5	475	arp_table[i].state = ETHARP_STATE_STABLE;
mbed714	0:98aadd37a5c5	476
mbed714	0:98aadd37a5c5	477	#if LWIP_SNMP
mbed714	0:98aadd37a5c5	478	/* record network interface */
mbed714	0:98aadd37a5c5	479	arp_table[i].netif = netif;
mbed714	0:98aadd37a5c5	480	#endif /* LWIP_SNMP */
mbed714	0:98aadd37a5c5	481	/* insert in SNMP ARP index tree */
mbed714	0:98aadd37a5c5	482	snmp_insert_arpidx_tree(netif, &arp_table[i].ipaddr);
mbed714	0:98aadd37a5c5	483
mbed714	0:98aadd37a5c5	484	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: updating stable entry %"S16_F"\n", (s16_t)i));
mbed714	0:98aadd37a5c5	485	/* update address */
mbed714	0:98aadd37a5c5	486	ETHADDR32_COPY(&arp_table[i].ethaddr, ethaddr);
mbed714	0:98aadd37a5c5	487	/* reset time stamp */
mbed714	0:98aadd37a5c5	488	arp_table[i].ctime = 0;
mbed714	0:98aadd37a5c5	489	#if ARP_QUEUEING
mbed714	0:98aadd37a5c5	490	/* this is where we will send out queued packets! */
mbed714	0:98aadd37a5c5	491	while (arp_table[i].q != NULL) {
mbed714	0:98aadd37a5c5	492	struct pbuf *p;
mbed714	0:98aadd37a5c5	493	/* remember remainder of queue */
mbed714	0:98aadd37a5c5	494	struct etharp_q_entry *q = arp_table[i].q;
mbed714	0:98aadd37a5c5	495	/* pop first item off the queue */
mbed714	0:98aadd37a5c5	496	arp_table[i].q = q->next;
mbed714	0:98aadd37a5c5	497	/* get the packet pointer */
mbed714	0:98aadd37a5c5	498	p = q->p;
mbed714	0:98aadd37a5c5	499	/* now queue entry can be freed */
mbed714	0:98aadd37a5c5	500	memp_free(MEMP_ARP_QUEUE, q);
mbed714	0:98aadd37a5c5	501	/* send the queued IP packet */
mbed714	0:98aadd37a5c5	502	etharp_send_ip(netif, p, (struct eth_addr*)(netif->hwaddr), ethaddr);
mbed714	0:98aadd37a5c5	503	/* free the queued IP packet */
mbed714	0:98aadd37a5c5	504	pbuf_free(p);
mbed714	0:98aadd37a5c5	505	}
mbed714	0:98aadd37a5c5	506	#endif /* ARP_QUEUEING */
mbed714	0:98aadd37a5c5	507	return ERR_OK;
mbed714	0:98aadd37a5c5	508	}
mbed714	0:98aadd37a5c5	509
mbed714	0:98aadd37a5c5	510	#if ETHARP_SUPPORT_STATIC_ENTRIES
mbed714	0:98aadd37a5c5	511	/** Add a new static entry to the ARP table. If an entry exists for the
mbed714	0:98aadd37a5c5	512	* specified IP address, this entry is overwritten.
mbed714	0:98aadd37a5c5	513	* If packets are queued for the specified IP address, they are sent out.
mbed714	0:98aadd37a5c5	514	*
mbed714	0:98aadd37a5c5	515	* @param ipaddr IP address for the new static entry
mbed714	0:98aadd37a5c5	516	* @param ethaddr ethernet address for the new static entry
mbed714	0:98aadd37a5c5	517	* @return @see return values of etharp_add_static_entry
mbed714	0:98aadd37a5c5	518	*/
mbed714	0:98aadd37a5c5	519	err_t
mbed714	0:98aadd37a5c5	520	etharp_add_static_entry(ip_addr_t ipaddr, struct eth_addr ethaddr)
mbed714	0:98aadd37a5c5	521	{
mbed714	0:98aadd37a5c5	522	struct netif *netif;
mbed714	0:98aadd37a5c5	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",
mbed714	0:98aadd37a5c5	524	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
mbed714	0:98aadd37a5c5	525	ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
mbed714	0:98aadd37a5c5	526	ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
mbed714	0:98aadd37a5c5	527
mbed714	0:98aadd37a5c5	528	netif = ip_route(ipaddr);
mbed714	0:98aadd37a5c5	529	if (netif == NULL) {
mbed714	0:98aadd37a5c5	530	return ERR_RTE;
mbed714	0:98aadd37a5c5	531	}
mbed714	0:98aadd37a5c5	532
mbed714	0:98aadd37a5c5	533	return update_arp_entry(netif, ipaddr, ethaddr, ETHARP_FLAG_TRY_HARD \| ETHARP_FLAG_STATIC_ENTRY);
mbed714	0:98aadd37a5c5	534	}
mbed714	0:98aadd37a5c5	535
mbed714	0:98aadd37a5c5	536	/** Remove a static entry from the ARP table previously added with a call to
mbed714	0:98aadd37a5c5	537	* etharp_add_static_entry.
mbed714	0:98aadd37a5c5	538	*
mbed714	0:98aadd37a5c5	539	* @param ipaddr IP address of the static entry to remove
mbed714	0:98aadd37a5c5	540	* @return ERR_OK: entry removed
mbed714	0:98aadd37a5c5	541	* ERR_MEM: entry wasn't found
mbed714	0:98aadd37a5c5	542	* ERR_ARG: entry wasn't a static entry but a dynamic one
mbed714	0:98aadd37a5c5	543	*/
mbed714	0:98aadd37a5c5	544	err_t
mbed714	0:98aadd37a5c5	545	etharp_remove_static_entry(ip_addr_t *ipaddr)
mbed714	0:98aadd37a5c5	546	{
mbed714	0:98aadd37a5c5	547	s8_t i;
mbed714	0:98aadd37a5c5	548	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_remove_static_entry: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
mbed714	0:98aadd37a5c5	549	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr)));
mbed714	0:98aadd37a5c5	550
mbed714	0:98aadd37a5c5	551	/* find or create ARP entry */
mbed714	0:98aadd37a5c5	552	i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
mbed714	0:98aadd37a5c5	553	/* bail out if no entry could be found */
mbed714	0:98aadd37a5c5	554	if (i < 0) {
mbed714	0:98aadd37a5c5	555	return (err_t)i;
mbed714	0:98aadd37a5c5	556	}
mbed714	0:98aadd37a5c5	557
mbed714	0:98aadd37a5c5	558	if ((arp_table[i].state != ETHARP_STATE_STABLE) \|\|
mbed714	0:98aadd37a5c5	559	(arp_table[i].static_entry == 0)) {
mbed714	0:98aadd37a5c5	560	/* entry wasn't a static entry, cannot remove it */
mbed714	0:98aadd37a5c5	561	return ERR_ARG;
mbed714	0:98aadd37a5c5	562	}
mbed714	0:98aadd37a5c5	563	/* entry found, free it */
mbed714	0:98aadd37a5c5	564	free_entry(i);
mbed714	0:98aadd37a5c5	565	return ERR_OK;
mbed714	0:98aadd37a5c5	566	}
mbed714	0:98aadd37a5c5	567	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
mbed714	0:98aadd37a5c5	568
mbed714	0:98aadd37a5c5	569	/**
mbed714	0:98aadd37a5c5	570	* Finds (stable) ethernet/IP address pair from ARP table
mbed714	0:98aadd37a5c5	571	* using interface and IP address index.
mbed714	0:98aadd37a5c5	572	* @note the addresses in the ARP table are in network order!
mbed714	0:98aadd37a5c5	573	*
mbed714	0:98aadd37a5c5	574	* @param netif points to interface index
mbed714	0:98aadd37a5c5	575	* @param ipaddr points to the (network order) IP address index
mbed714	0:98aadd37a5c5	576	* @param eth_ret points to return pointer
mbed714	0:98aadd37a5c5	577	* @param ip_ret points to return pointer
mbed714	0:98aadd37a5c5	578	* @return table index if found, -1 otherwise
mbed714	0:98aadd37a5c5	579	*/
mbed714	0:98aadd37a5c5	580	s8_t
mbed714	0:98aadd37a5c5	581	etharp_find_addr(struct netif netif, ip_addr_t ipaddr,
mbed714	0:98aadd37a5c5	582	struct eth_addr eth_ret, ip_addr_t ip_ret)
mbed714	0:98aadd37a5c5	583	{
mbed714	0:98aadd37a5c5	584	s8_t i;
mbed714	0:98aadd37a5c5	585
mbed714	0:98aadd37a5c5	586	LWIP_ASSERT("eth_ret != NULL && ip_ret != NULL",
mbed714	0:98aadd37a5c5	587	eth_ret != NULL && ip_ret != NULL);
mbed714	0:98aadd37a5c5	588
mbed714	0:98aadd37a5c5	589	LWIP_UNUSED_ARG(netif);
mbed714	0:98aadd37a5c5	590
mbed714	0:98aadd37a5c5	591	i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
mbed714	0:98aadd37a5c5	592	if((i >= 0) && arp_table[i].state == ETHARP_STATE_STABLE) {
mbed714	0:98aadd37a5c5	593	*eth_ret = &arp_table[i].ethaddr;
mbed714	0:98aadd37a5c5	594	*ip_ret = &arp_table[i].ipaddr;
mbed714	0:98aadd37a5c5	595	return i;
mbed714	0:98aadd37a5c5	596	}
mbed714	0:98aadd37a5c5	597	return -1;
mbed714	0:98aadd37a5c5	598	}
mbed714	0:98aadd37a5c5	599
mbed714	0:98aadd37a5c5	600	#if ETHARP_TRUST_IP_MAC
mbed714	0:98aadd37a5c5	601	/**
mbed714	0:98aadd37a5c5	602	* Updates the ARP table using the given IP packet.
mbed714	0:98aadd37a5c5	603	*
mbed714	0:98aadd37a5c5	604	* Uses the incoming IP packet's source address to update the
mbed714	0:98aadd37a5c5	605	* ARP cache for the local network. The function does not alter
mbed714	0:98aadd37a5c5	606	* or free the packet. This function must be called before the
mbed714	0:98aadd37a5c5	607	* packet p is passed to the IP layer.
mbed714	0:98aadd37a5c5	608	*
mbed714	0:98aadd37a5c5	609	* @param netif The lwIP network interface on which the IP packet pbuf arrived.
mbed714	0:98aadd37a5c5	610	* @param p The IP packet that arrived on netif.
mbed714	0:98aadd37a5c5	611	*
mbed714	0:98aadd37a5c5	612	* @return NULL
mbed714	0:98aadd37a5c5	613	*
mbed714	0:98aadd37a5c5	614	* @see pbuf_free()
mbed714	0:98aadd37a5c5	615	*/
mbed714	0:98aadd37a5c5	616	static void
mbed714	0:98aadd37a5c5	617	etharp_ip_input(struct netif netif, struct pbuf p)
mbed714	0:98aadd37a5c5	618	{
mbed714	0:98aadd37a5c5	619	struct eth_hdr *ethhdr;
mbed714	0:98aadd37a5c5	620	struct ip_hdr *iphdr;
mbed714	0:98aadd37a5c5	621	ip_addr_t iphdr_src;
mbed714	0:98aadd37a5c5	622	LWIP_ERROR("netif != NULL", (netif != NULL), return;);
mbed714	0:98aadd37a5c5	623
mbed714	0:98aadd37a5c5	624	/* Only insert an entry if the source IP address of the
mbed714	0:98aadd37a5c5	625	incoming IP packet comes from a host on the local network. */
mbed714	0:98aadd37a5c5	626	ethhdr = (struct eth_hdr *)p->payload;
mbed714	0:98aadd37a5c5	627	iphdr = (struct ip_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
mbed714	0:98aadd37a5c5	628	#if ETHARP_SUPPORT_VLAN
mbed714	0:98aadd37a5c5	629	if (ethhdr->type == ETHTYPE_VLAN) {
mbed714	0:98aadd37a5c5	630	iphdr = (struct ip_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
mbed714	0:98aadd37a5c5	631	}
mbed714	0:98aadd37a5c5	632	#endif /* ETHARP_SUPPORT_VLAN */
mbed714	0:98aadd37a5c5	633
mbed714	0:98aadd37a5c5	634	ip_addr_copy(iphdr_src, iphdr->src);
mbed714	0:98aadd37a5c5	635
mbed714	0:98aadd37a5c5	636	/* source is not on the local network? */
mbed714	0:98aadd37a5c5	637	if (!ip_addr_netcmp(&iphdr_src, &(netif->ip_addr), &(netif->netmask))) {
mbed714	0:98aadd37a5c5	638	/* do nothing */
mbed714	0:98aadd37a5c5	639	return;
mbed714	0:98aadd37a5c5	640	}
mbed714	0:98aadd37a5c5	641
mbed714	0:98aadd37a5c5	642	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_ip_input: updating ETHARP table.\n"));
mbed714	0:98aadd37a5c5	643	/* update the source IP address in the cache, if present */
mbed714	0:98aadd37a5c5	644	/* @todo We could use ETHARP_FLAG_TRY_HARD if we think we are going to talk
mbed714	0:98aadd37a5c5	645	* back soon (for example, if the destination IP address is ours. */
mbed714	0:98aadd37a5c5	646	update_arp_entry(netif, &iphdr_src, &(ethhdr->src), ETHARP_FLAG_FIND_ONLY);
mbed714	0:98aadd37a5c5	647	}
mbed714	0:98aadd37a5c5	648	#endif /* ETHARP_TRUST_IP_MAC */
mbed714	0:98aadd37a5c5	649
mbed714	0:98aadd37a5c5	650	/**
mbed714	0:98aadd37a5c5	651	* Responds to ARP requests to us. Upon ARP replies to us, add entry to cache
mbed714	0:98aadd37a5c5	652	* send out queued IP packets. Updates cache with snooped address pairs.
mbed714	0:98aadd37a5c5	653	*
mbed714	0:98aadd37a5c5	654	* Should be called for incoming ARP packets. The pbuf in the argument
mbed714	0:98aadd37a5c5	655	* is freed by this function.
mbed714	0:98aadd37a5c5	656	*
mbed714	0:98aadd37a5c5	657	* @param netif The lwIP network interface on which the ARP packet pbuf arrived.
mbed714	0:98aadd37a5c5	658	* @param ethaddr Ethernet address of netif.
mbed714	0:98aadd37a5c5	659	* @param p The ARP packet that arrived on netif. Is freed by this function.
mbed714	0:98aadd37a5c5	660	*
mbed714	0:98aadd37a5c5	661	* @return NULL
mbed714	0:98aadd37a5c5	662	*
mbed714	0:98aadd37a5c5	663	* @see pbuf_free()
mbed714	0:98aadd37a5c5	664	*/
mbed714	0:98aadd37a5c5	665	static void
mbed714	0:98aadd37a5c5	666	etharp_arp_input(struct netif netif, struct eth_addr ethaddr, struct pbuf *p)
mbed714	0:98aadd37a5c5	667	{
mbed714	0:98aadd37a5c5	668	struct etharp_hdr *hdr;
mbed714	0:98aadd37a5c5	669	struct eth_hdr *ethhdr;
mbed714	0:98aadd37a5c5	670	/* these are aligned properly, whereas the ARP header fields might not be */
mbed714	0:98aadd37a5c5	671	ip_addr_t sipaddr, dipaddr;
mbed714	0:98aadd37a5c5	672	u8_t for_us;
mbed714	0:98aadd37a5c5	673	#if LWIP_AUTOIP
mbed714	0:98aadd37a5c5	674	const u8_t * ethdst_hwaddr;
mbed714	0:98aadd37a5c5	675	#endif /* LWIP_AUTOIP */
mbed714	0:98aadd37a5c5	676
mbed714	0:98aadd37a5c5	677	LWIP_ERROR("netif != NULL", (netif != NULL), return;);
mbed714	0:98aadd37a5c5	678
mbed714	0:98aadd37a5c5	679	/* drop short ARP packets: we have to check for p->len instead of p->tot_len here
mbed714	0:98aadd37a5c5	680	since a struct etharp_hdr is pointed to p->payload, so it musn't be chained! */
mbed714	0:98aadd37a5c5	681	if (p->len < SIZEOF_ETHARP_PACKET) {
mbed714	0:98aadd37a5c5	682	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_WARNING,
mbed714	0:98aadd37a5c5	683	("etharp_arp_input: packet dropped, too short (%"S16_F"/%"S16_F")\n", p->tot_len,
mbed714	0:98aadd37a5c5	684	(s16_t)SIZEOF_ETHARP_PACKET));
mbed714	0:98aadd37a5c5	685	ETHARP_STATS_INC(etharp.lenerr);
mbed714	0:98aadd37a5c5	686	ETHARP_STATS_INC(etharp.drop);
mbed714	0:98aadd37a5c5	687	pbuf_free(p);
mbed714	0:98aadd37a5c5	688	return;
mbed714	0:98aadd37a5c5	689	}
mbed714	0:98aadd37a5c5	690
mbed714	0:98aadd37a5c5	691	ethhdr = (struct eth_hdr *)p->payload;
mbed714	0:98aadd37a5c5	692	hdr = (struct etharp_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
mbed714	0:98aadd37a5c5	693	#if ETHARP_SUPPORT_VLAN
mbed714	0:98aadd37a5c5	694	if (ethhdr->type == ETHTYPE_VLAN) {
mbed714	0:98aadd37a5c5	695	hdr = (struct etharp_hdr )(((u8_t)ethhdr) + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
mbed714	0:98aadd37a5c5	696	}
mbed714	0:98aadd37a5c5	697	#endif /* ETHARP_SUPPORT_VLAN */
mbed714	0:98aadd37a5c5	698
mbed714	0:98aadd37a5c5	699	/* RFC 826 "Packet Reception": */
mbed714	0:98aadd37a5c5	700	if ((hdr->hwtype != PP_HTONS(HWTYPE_ETHERNET)) \|\|
mbed714	0:98aadd37a5c5	701	(hdr->hwlen != ETHARP_HWADDR_LEN) \|\|
mbed714	0:98aadd37a5c5	702	(hdr->protolen != sizeof(ip_addr_t)) \|\|
mbed714	0:98aadd37a5c5	703	(hdr->proto != PP_HTONS(ETHTYPE_IP)) \|\|
mbed714	0:98aadd37a5c5	704	(ethhdr->type != PP_HTONS(ETHTYPE_ARP))) {
mbed714	0:98aadd37a5c5	705	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_WARNING,
mbed714	0:98aadd37a5c5	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",
mbed714	0:98aadd37a5c5	707	hdr->hwtype, hdr->hwlen, hdr->proto, hdr->protolen, ethhdr->type));
mbed714	0:98aadd37a5c5	708	ETHARP_STATS_INC(etharp.proterr);
mbed714	0:98aadd37a5c5	709	ETHARP_STATS_INC(etharp.drop);
mbed714	0:98aadd37a5c5	710	pbuf_free(p);
mbed714	0:98aadd37a5c5	711	return;
mbed714	0:98aadd37a5c5	712	}
mbed714	0:98aadd37a5c5	713	ETHARP_STATS_INC(etharp.recv);
mbed714	0:98aadd37a5c5	714
mbed714	0:98aadd37a5c5	715	#if LWIP_AUTOIP
mbed714	0:98aadd37a5c5	716	/* We have to check if a host already has configured our random
mbed714	0:98aadd37a5c5	717	* created link local address and continously check if there is
mbed714	0:98aadd37a5c5	718	* a host with this IP-address so we can detect collisions */
mbed714	0:98aadd37a5c5	719	autoip_arp_reply(netif, hdr);
mbed714	0:98aadd37a5c5	720	#endif /* LWIP_AUTOIP */
mbed714	0:98aadd37a5c5	721
mbed714	0:98aadd37a5c5	722	/* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
mbed714	0:98aadd37a5c5	723	* structure packing (not using structure copy which breaks strict-aliasing rules). */
mbed714	0:98aadd37a5c5	724	IPADDR2_COPY(&sipaddr, &hdr->sipaddr);
mbed714	0:98aadd37a5c5	725	IPADDR2_COPY(&dipaddr, &hdr->dipaddr);
mbed714	0:98aadd37a5c5	726
mbed714	0:98aadd37a5c5	727	/* this interface is not configured? */
mbed714	0:98aadd37a5c5	728	if (ip_addr_isany(&netif->ip_addr)) {
mbed714	0:98aadd37a5c5	729	for_us = 0;
mbed714	0:98aadd37a5c5	730	} else {
mbed714	0:98aadd37a5c5	731	/* ARP packet directed to us? */
mbed714	0:98aadd37a5c5	732	for_us = (u8_t)ip_addr_cmp(&dipaddr, &(netif->ip_addr));
mbed714	0:98aadd37a5c5	733	}
mbed714	0:98aadd37a5c5	734
mbed714	0:98aadd37a5c5	735	/* ARP message directed to us?
mbed714	0:98aadd37a5c5	736	-> add IP address in ARP cache; assume requester wants to talk to us,
mbed714	0:98aadd37a5c5	737	can result in directly sending the queued packets for this host.
mbed714	0:98aadd37a5c5	738	ARP message not directed to us?
mbed714	0:98aadd37a5c5	739	-> update the source IP address in the cache, if present */
mbed714	0:98aadd37a5c5	740	update_arp_entry(netif, &sipaddr, &(hdr->shwaddr),
mbed714	0:98aadd37a5c5	741	for_us ? ETHARP_FLAG_TRY_HARD : ETHARP_FLAG_FIND_ONLY);
mbed714	0:98aadd37a5c5	742
mbed714	0:98aadd37a5c5	743	/* now act on the message itself */
mbed714	0:98aadd37a5c5	744	switch (hdr->opcode) {
mbed714	0:98aadd37a5c5	745	/* ARP request? */
mbed714	0:98aadd37a5c5	746	case PP_HTONS(ARP_REQUEST):
mbed714	0:98aadd37a5c5	747	/* ARP request. If it asked for our address, we send out a
mbed714	0:98aadd37a5c5	748	* reply. In any case, we time-stamp any existing ARP entry,
mbed714	0:98aadd37a5c5	749	* and possiby send out an IP packet that was queued on it. */
mbed714	0:98aadd37a5c5	750
mbed714	0:98aadd37a5c5	751	LWIP_DEBUGF (ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP request\n"));
mbed714	0:98aadd37a5c5	752	/* ARP request for our address? */
mbed714	0:98aadd37a5c5	753	if (for_us) {
mbed714	0:98aadd37a5c5	754
mbed714	0:98aadd37a5c5	755	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: replying to ARP request for our IP address\n"));
mbed714	0:98aadd37a5c5	756	/* Re-use pbuf to send ARP reply.
mbed714	0:98aadd37a5c5	757	Since we are re-using an existing pbuf, we can't call etharp_raw since
mbed714	0:98aadd37a5c5	758	that would allocate a new pbuf. */
mbed714	0:98aadd37a5c5	759	hdr->opcode = htons(ARP_REPLY);
mbed714	0:98aadd37a5c5	760
mbed714	0:98aadd37a5c5	761	IPADDR2_COPY(&hdr->dipaddr, &hdr->sipaddr);
mbed714	0:98aadd37a5c5	762	IPADDR2_COPY(&hdr->sipaddr, &netif->ip_addr);
mbed714	0:98aadd37a5c5	763
mbed714	0:98aadd37a5c5	764	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
mbed714	0:98aadd37a5c5	765	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
mbed714	0:98aadd37a5c5	766	#if LWIP_AUTOIP
mbed714	0:98aadd37a5c5	767	/* If we are using Link-Local, all ARP packets that contain a Link-Local
mbed714	0:98aadd37a5c5	768	* 'sender IP address' MUST be sent using link-layer broadcast instead of
mbed714	0:98aadd37a5c5	769	* link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
mbed714	0:98aadd37a5c5	770	ethdst_hwaddr = ip_addr_islinklocal(&netif->ip_addr) ? (u8_t*)(ethbroadcast.addr) : hdr->shwaddr.addr;
mbed714	0:98aadd37a5c5	771	#endif /* LWIP_AUTOIP */
mbed714	0:98aadd37a5c5	772
mbed714	0:98aadd37a5c5	773	ETHADDR16_COPY(&hdr->dhwaddr, &hdr->shwaddr);
mbed714	0:98aadd37a5c5	774	#if LWIP_AUTOIP
mbed714	0:98aadd37a5c5	775	ETHADDR16_COPY(&ethhdr->dest, ethdst_hwaddr);
mbed714	0:98aadd37a5c5	776	#else /* LWIP_AUTOIP */
mbed714	0:98aadd37a5c5	777	ETHADDR16_COPY(&ethhdr->dest, &hdr->shwaddr);
mbed714	0:98aadd37a5c5	778	#endif /* LWIP_AUTOIP */
mbed714	0:98aadd37a5c5	779	ETHADDR16_COPY(&hdr->shwaddr, ethaddr);
mbed714	0:98aadd37a5c5	780	ETHADDR16_COPY(&ethhdr->src, ethaddr);
mbed714	0:98aadd37a5c5	781
mbed714	0:98aadd37a5c5	782	/* hwtype, hwaddr_len, proto, protolen and the type in the ethernet header
mbed714	0:98aadd37a5c5	783	are already correct, we tested that before */
mbed714	0:98aadd37a5c5	784
mbed714	0:98aadd37a5c5	785	/* return ARP reply */
mbed714	0:98aadd37a5c5	786	netif->linkoutput(netif, p);
mbed714	0:98aadd37a5c5	787	/* we are not configured? */
mbed714	0:98aadd37a5c5	788	} else if (ip_addr_isany(&netif->ip_addr)) {
mbed714	0:98aadd37a5c5	789	/* { for_us == 0 and netif->ip_addr.addr == 0 } */
mbed714	0:98aadd37a5c5	790	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: we are unconfigured, ARP request ignored.\n"));
mbed714	0:98aadd37a5c5	791	/* request was not directed to us */
mbed714	0:98aadd37a5c5	792	} else {
mbed714	0:98aadd37a5c5	793	/* { for_us == 0 and netif->ip_addr.addr != 0 } */
mbed714	0:98aadd37a5c5	794	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: ARP request was not for us.\n"));
mbed714	0:98aadd37a5c5	795	}
mbed714	0:98aadd37a5c5	796	break;
mbed714	0:98aadd37a5c5	797	case PP_HTONS(ARP_REPLY):
mbed714	0:98aadd37a5c5	798	/* ARP reply. We already updated the ARP cache earlier. */
mbed714	0:98aadd37a5c5	799	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP reply\n"));
mbed714	0:98aadd37a5c5	800	#if (LWIP_DHCP && DHCP_DOES_ARP_CHECK)
mbed714	0:98aadd37a5c5	801	/* DHCP wants to know about ARP replies from any host with an
mbed714	0:98aadd37a5c5	802	* IP address also offered to us by the DHCP server. We do not
mbed714	0:98aadd37a5c5	803	* want to take a duplicate IP address on a single network.
mbed714	0:98aadd37a5c5	804	* @todo How should we handle redundant (fail-over) interfaces? */
mbed714	0:98aadd37a5c5	805	dhcp_arp_reply(netif, &sipaddr);
mbed714	0:98aadd37a5c5	806	#endif /* (LWIP_DHCP && DHCP_DOES_ARP_CHECK) */
mbed714	0:98aadd37a5c5	807	break;
mbed714	0:98aadd37a5c5	808	default:
mbed714	0:98aadd37a5c5	809	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: ARP unknown opcode type %"S16_F"\n", htons(hdr->opcode)));
mbed714	0:98aadd37a5c5	810	ETHARP_STATS_INC(etharp.err);
mbed714	0:98aadd37a5c5	811	break;
mbed714	0:98aadd37a5c5	812	}
mbed714	0:98aadd37a5c5	813	/* free ARP packet */
mbed714	0:98aadd37a5c5	814	pbuf_free(p);
mbed714	0:98aadd37a5c5	815	}
mbed714	0:98aadd37a5c5	816
mbed714	0:98aadd37a5c5	817	/**
mbed714	0:98aadd37a5c5	818	* Resolve and fill-in Ethernet address header for outgoing IP packet.
mbed714	0:98aadd37a5c5	819	*
mbed714	0:98aadd37a5c5	820	* For IP multicast and broadcast, corresponding Ethernet addresses
mbed714	0:98aadd37a5c5	821	* are selected and the packet is transmitted on the link.
mbed714	0:98aadd37a5c5	822	*
mbed714	0:98aadd37a5c5	823	* For unicast addresses, the packet is submitted to etharp_query(). In
mbed714	0:98aadd37a5c5	824	* case the IP address is outside the local network, the IP address of
mbed714	0:98aadd37a5c5	825	* the gateway is used.
mbed714	0:98aadd37a5c5	826	*
mbed714	0:98aadd37a5c5	827	* @param netif The lwIP network interface which the IP packet will be sent on.
mbed714	0:98aadd37a5c5	828	* @param q The pbuf(s) containing the IP packet to be sent.
mbed714	0:98aadd37a5c5	829	* @param ipaddr The IP address of the packet destination.
mbed714	0:98aadd37a5c5	830	*
mbed714	0:98aadd37a5c5	831	* @return
mbed714	0:98aadd37a5c5	832	* - ERR_RTE No route to destination (no gateway to external networks),
mbed714	0:98aadd37a5c5	833	* or the return type of either etharp_query() or etharp_send_ip().
mbed714	0:98aadd37a5c5	834	*/
mbed714	0:98aadd37a5c5	835	err_t
mbed714	0:98aadd37a5c5	836	etharp_output(struct netif netif, struct pbuf q, ip_addr_t *ipaddr)
mbed714	0:98aadd37a5c5	837	{
mbed714	0:98aadd37a5c5	838	struct eth_addr *dest, mcastaddr;
mbed714	0:98aadd37a5c5	839
mbed714	0:98aadd37a5c5	840	/* make room for Ethernet header - should not fail */
mbed714	0:98aadd37a5c5	841	if (pbuf_header(q, sizeof(struct eth_hdr)) != 0) {
mbed714	0:98aadd37a5c5	842	/* bail out */
mbed714	0:98aadd37a5c5	843	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_SERIOUS,
mbed714	0:98aadd37a5c5	844	("etharp_output: could not allocate room for header.\n"));
mbed714	0:98aadd37a5c5	845	LINK_STATS_INC(link.lenerr);
mbed714	0:98aadd37a5c5	846	return ERR_BUF;
mbed714	0:98aadd37a5c5	847	}
mbed714	0:98aadd37a5c5	848
mbed714	0:98aadd37a5c5	849	/* assume unresolved Ethernet address */
mbed714	0:98aadd37a5c5	850	dest = NULL;
mbed714	0:98aadd37a5c5	851	/* Determine on destination hardware address. Broadcasts and multicasts
mbed714	0:98aadd37a5c5	852	* are special, other IP addresses are looked up in the ARP table. */
mbed714	0:98aadd37a5c5	853
mbed714	0:98aadd37a5c5	854	/* broadcast destination IP address? */
mbed714	0:98aadd37a5c5	855	if (ip_addr_isbroadcast(ipaddr, netif)) {
mbed714	0:98aadd37a5c5	856	/* broadcast on Ethernet also */
mbed714	0:98aadd37a5c5	857	dest = (struct eth_addr *)&ethbroadcast;
mbed714	0:98aadd37a5c5	858	/* multicast destination IP address? */
mbed714	0:98aadd37a5c5	859	} else if (ip_addr_ismulticast(ipaddr)) {
mbed714	0:98aadd37a5c5	860	/* Hash IP multicast address to MAC address.*/
mbed714	0:98aadd37a5c5	861	mcastaddr.addr[0] = 0x01;
mbed714	0:98aadd37a5c5	862	mcastaddr.addr[1] = 0x00;
mbed714	0:98aadd37a5c5	863	mcastaddr.addr[2] = 0x5e;
mbed714	0:98aadd37a5c5	864	mcastaddr.addr[3] = ip4_addr2(ipaddr) & 0x7f;
mbed714	0:98aadd37a5c5	865	mcastaddr.addr[4] = ip4_addr3(ipaddr);
mbed714	0:98aadd37a5c5	866	mcastaddr.addr[5] = ip4_addr4(ipaddr);
mbed714	0:98aadd37a5c5	867	/* destination Ethernet address is multicast */
mbed714	0:98aadd37a5c5	868	dest = &mcastaddr;
mbed714	0:98aadd37a5c5	869	/* unicast destination IP address? */
mbed714	0:98aadd37a5c5	870	} else {
mbed714	0:98aadd37a5c5	871	/* outside local network? */
mbed714	0:98aadd37a5c5	872	if (!ip_addr_netcmp(ipaddr, &(netif->ip_addr), &(netif->netmask)) &&
mbed714	0:98aadd37a5c5	873	!ip_addr_islinklocal(ipaddr)) {
mbed714	0:98aadd37a5c5	874	/* interface has default gateway? */
mbed714	0:98aadd37a5c5	875	if (!ip_addr_isany(&netif->gw)) {
mbed714	0:98aadd37a5c5	876	/* send to hardware address of default gateway IP address */
mbed714	0:98aadd37a5c5	877	ipaddr = &(netif->gw);
mbed714	0:98aadd37a5c5	878	/* no default gateway available */
mbed714	0:98aadd37a5c5	879	} else {
mbed714	0:98aadd37a5c5	880	/* no route to destination error (default gateway missing) */
mbed714	0:98aadd37a5c5	881	return ERR_RTE;
mbed714	0:98aadd37a5c5	882	}
mbed714	0:98aadd37a5c5	883	}
mbed714	0:98aadd37a5c5	884	#if LWIP_NETIF_HWADDRHINT
mbed714	0:98aadd37a5c5	885	if (netif->addr_hint != NULL) {
mbed714	0:98aadd37a5c5	886	/* per-pcb cached entry was given */
mbed714	0:98aadd37a5c5	887	u8_t etharp_cached_entry = *(netif->addr_hint);
mbed714	0:98aadd37a5c5	888	if (etharp_cached_entry < ARP_TABLE_SIZE) {
mbed714	0:98aadd37a5c5	889	#endif /* LWIP_NETIF_HWADDRHINT */
mbed714	0:98aadd37a5c5	890	if ((arp_table[etharp_cached_entry].state == ETHARP_STATE_STABLE) &&
mbed714	0:98aadd37a5c5	891	(ip_addr_cmp(ipaddr, &arp_table[etharp_cached_entry].ipaddr))) {
mbed714	0:98aadd37a5c5	892	/* the per-pcb-cached entry is stable and the right one! */
mbed714	0:98aadd37a5c5	893	ETHARP_STATS_INC(etharp.cachehit);
mbed714	0:98aadd37a5c5	894	return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr),
mbed714	0:98aadd37a5c5	895	&arp_table[etharp_cached_entry].ethaddr);
mbed714	0:98aadd37a5c5	896	}
mbed714	0:98aadd37a5c5	897	#if LWIP_NETIF_HWADDRHINT
mbed714	0:98aadd37a5c5	898	}
mbed714	0:98aadd37a5c5	899	}
mbed714	0:98aadd37a5c5	900	#endif /* LWIP_NETIF_HWADDRHINT */
mbed714	0:98aadd37a5c5	901	/* queue on destination Ethernet address belonging to ipaddr */
mbed714	0:98aadd37a5c5	902	return etharp_query(netif, ipaddr, q);
mbed714	0:98aadd37a5c5	903	}
mbed714	0:98aadd37a5c5	904
mbed714	0:98aadd37a5c5	905	/* continuation for multicast/broadcast destinations */
mbed714	0:98aadd37a5c5	906	/* obtain source Ethernet address of the given interface */
mbed714	0:98aadd37a5c5	907	/* send packet directly on the link */
mbed714	0:98aadd37a5c5	908	return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr), dest);
mbed714	0:98aadd37a5c5	909	}
mbed714	0:98aadd37a5c5	910
mbed714	0:98aadd37a5c5	911	/**
mbed714	0:98aadd37a5c5	912	* Send an ARP request for the given IP address and/or queue a packet.
mbed714	0:98aadd37a5c5	913	*
mbed714	0:98aadd37a5c5	914	* If the IP address was not yet in the cache, a pending ARP cache entry
mbed714	0:98aadd37a5c5	915	* is added and an ARP request is sent for the given address. The packet
mbed714	0:98aadd37a5c5	916	* is queued on this entry.
mbed714	0:98aadd37a5c5	917	*
mbed714	0:98aadd37a5c5	918	* If the IP address was already pending in the cache, a new ARP request
mbed714	0:98aadd37a5c5	919	* is sent for the given address. The packet is queued on this entry.
mbed714	0:98aadd37a5c5	920	*
mbed714	0:98aadd37a5c5	921	* If the IP address was already stable in the cache, and a packet is
mbed714	0:98aadd37a5c5	922	* given, it is directly sent and no ARP request is sent out.
mbed714	0:98aadd37a5c5	923	*
mbed714	0:98aadd37a5c5	924	* If the IP address was already stable in the cache, and no packet is
mbed714	0:98aadd37a5c5	925	* given, an ARP request is sent out.
mbed714	0:98aadd37a5c5	926	*
mbed714	0:98aadd37a5c5	927	* @param netif The lwIP network interface on which ipaddr
mbed714	0:98aadd37a5c5	928	* must be queried for.
mbed714	0:98aadd37a5c5	929	* @param ipaddr The IP address to be resolved.
mbed714	0:98aadd37a5c5	930	* @param q If non-NULL, a pbuf that must be delivered to the IP address.
mbed714	0:98aadd37a5c5	931	* q is not freed by this function.
mbed714	0:98aadd37a5c5	932	*
mbed714	0:98aadd37a5c5	933	* @note q must only be ONE packet, not a packet queue!
mbed714	0:98aadd37a5c5	934	*
mbed714	0:98aadd37a5c5	935	* @return
mbed714	0:98aadd37a5c5	936	* - ERR_BUF Could not make room for Ethernet header.
mbed714	0:98aadd37a5c5	937	* - ERR_MEM Hardware address unknown, and no more ARP entries available
mbed714	0:98aadd37a5c5	938	* to query for address or queue the packet.
mbed714	0:98aadd37a5c5	939	* - ERR_MEM Could not queue packet due to memory shortage.
mbed714	0:98aadd37a5c5	940	* - ERR_RTE No route to destination (no gateway to external networks).
mbed714	0:98aadd37a5c5	941	* - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
mbed714	0:98aadd37a5c5	942	*
mbed714	0:98aadd37a5c5	943	*/
mbed714	0:98aadd37a5c5	944	err_t
mbed714	0:98aadd37a5c5	945	etharp_query(struct netif netif, ip_addr_t ipaddr, struct pbuf *q)
mbed714	0:98aadd37a5c5	946	{
mbed714	0:98aadd37a5c5	947	struct eth_addr * srcaddr = (struct eth_addr *)netif->hwaddr;
mbed714	0:98aadd37a5c5	948	err_t result = ERR_MEM;
mbed714	0:98aadd37a5c5	949	s8_t i; /* ARP entry index */
mbed714	0:98aadd37a5c5	950
mbed714	0:98aadd37a5c5	951	/* non-unicast address? */
mbed714	0:98aadd37a5c5	952	if (ip_addr_isbroadcast(ipaddr, netif) \|\|
mbed714	0:98aadd37a5c5	953	ip_addr_ismulticast(ipaddr) \|\|
mbed714	0:98aadd37a5c5	954	ip_addr_isany(ipaddr)) {
mbed714	0:98aadd37a5c5	955	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: will not add non-unicast IP address to ARP cache\n"));
mbed714	0:98aadd37a5c5	956	return ERR_ARG;
mbed714	0:98aadd37a5c5	957	}
mbed714	0:98aadd37a5c5	958
mbed714	0:98aadd37a5c5	959	/* find entry in ARP cache, ask to create entry if queueing packet */
mbed714	0:98aadd37a5c5	960	i = find_entry(ipaddr, ETHARP_FLAG_TRY_HARD);
mbed714	0:98aadd37a5c5	961
mbed714	0:98aadd37a5c5	962	/* could not find or create entry? */
mbed714	0:98aadd37a5c5	963	if (i < 0) {
mbed714	0:98aadd37a5c5	964	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: could not create ARP entry\n"));
mbed714	0:98aadd37a5c5	965	if (q) {
mbed714	0:98aadd37a5c5	966	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: packet dropped\n"));
mbed714	0:98aadd37a5c5	967	ETHARP_STATS_INC(etharp.memerr);
mbed714	0:98aadd37a5c5	968	}
mbed714	0:98aadd37a5c5	969	return (err_t)i;
mbed714	0:98aadd37a5c5	970	}
mbed714	0:98aadd37a5c5	971
mbed714	0:98aadd37a5c5	972	/* mark a fresh entry as pending (we just sent a request) */
mbed714	0:98aadd37a5c5	973	if (arp_table[i].state == ETHARP_STATE_EMPTY) {
mbed714	0:98aadd37a5c5	974	arp_table[i].state = ETHARP_STATE_PENDING;
mbed714	0:98aadd37a5c5	975	}
mbed714	0:98aadd37a5c5	976
mbed714	0:98aadd37a5c5	977	/* { i is either a STABLE or (new or existing) PENDING entry } */
mbed714	0:98aadd37a5c5	978	LWIP_ASSERT("arp_table[i].state == PENDING or STABLE",
mbed714	0:98aadd37a5c5	979	((arp_table[i].state == ETHARP_STATE_PENDING) \|\|
mbed714	0:98aadd37a5c5	980	(arp_table[i].state == ETHARP_STATE_STABLE)));
mbed714	0:98aadd37a5c5	981
mbed714	0:98aadd37a5c5	982	/* do we have a pending entry? or an implicit query request? */
mbed714	0:98aadd37a5c5	983	if ((arp_table[i].state == ETHARP_STATE_PENDING) \|\| (q == NULL)) {
mbed714	0:98aadd37a5c5	984	/* try to resolve it; send out ARP request */
mbed714	0:98aadd37a5c5	985	result = etharp_request(netif, ipaddr);
mbed714	0:98aadd37a5c5	986	if (result != ERR_OK) {
mbed714	0:98aadd37a5c5	987	/* ARP request couldn't be sent */
mbed714	0:98aadd37a5c5	988	/* We don't re-send arp request in etharp_tmr, but we still queue packets,
mbed714	0:98aadd37a5c5	989	since this failure could be temporary, and the next packet calling
mbed714	0:98aadd37a5c5	990	etharp_query again could lead to sending the queued packets. */
mbed714	0:98aadd37a5c5	991	}
mbed714	0:98aadd37a5c5	992	if (q == NULL) {
mbed714	0:98aadd37a5c5	993	return result;
mbed714	0:98aadd37a5c5	994	}
mbed714	0:98aadd37a5c5	995	}
mbed714	0:98aadd37a5c5	996
mbed714	0:98aadd37a5c5	997	/* packet given? */
mbed714	0:98aadd37a5c5	998	LWIP_ASSERT("q != NULL", q != NULL);
mbed714	0:98aadd37a5c5	999	/* stable entry? */
mbed714	0:98aadd37a5c5	1000	if (arp_table[i].state == ETHARP_STATE_STABLE) {
mbed714	0:98aadd37a5c5	1001	/* we have a valid IP->Ethernet address mapping */
mbed714	0:98aadd37a5c5	1002	ETHARP_SET_HINT(netif, i);
mbed714	0:98aadd37a5c5	1003	/* send the packet */
mbed714	0:98aadd37a5c5	1004	result = etharp_send_ip(netif, q, srcaddr, &(arp_table[i].ethaddr));
mbed714	0:98aadd37a5c5	1005	/* pending entry? (either just created or already pending */
mbed714	0:98aadd37a5c5	1006	} else if (arp_table[i].state == ETHARP_STATE_PENDING) {
mbed714	0:98aadd37a5c5	1007	#if ARP_QUEUEING /* queue the given q packet */
mbed714	0:98aadd37a5c5	1008	struct pbuf *p;
mbed714	0:98aadd37a5c5	1009	int copy_needed = 0;
mbed714	0:98aadd37a5c5	1010	/* IF q includes a PBUF_REF, PBUF_POOL or PBUF_RAM, we have no choice but
mbed714	0:98aadd37a5c5	1011	* to copy the whole queue into a new PBUF_RAM (see bug #11400)
mbed714	0:98aadd37a5c5	1012	* PBUF_ROMs can be left as they are, since ROM must not get changed. */
mbed714	0:98aadd37a5c5	1013	p = q;
mbed714	0:98aadd37a5c5	1014	while (p) {
mbed714	0:98aadd37a5c5	1015	LWIP_ASSERT("no packet queues allowed!", (p->len != p->tot_len) \|\| (p->next == 0));
mbed714	0:98aadd37a5c5	1016	if(p->type != PBUF_ROM) {
mbed714	0:98aadd37a5c5	1017	copy_needed = 1;
mbed714	0:98aadd37a5c5	1018	break;
mbed714	0:98aadd37a5c5	1019	}
mbed714	0:98aadd37a5c5	1020	p = p->next;
mbed714	0:98aadd37a5c5	1021	}
mbed714	0:98aadd37a5c5	1022	if(copy_needed) {
mbed714	0:98aadd37a5c5	1023	/* copy the whole packet into new pbufs */
mbed714	0:98aadd37a5c5	1024	p = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
mbed714	0:98aadd37a5c5	1025	if(p != NULL) {
mbed714	0:98aadd37a5c5	1026	if (pbuf_copy(p, q) != ERR_OK) {
mbed714	0:98aadd37a5c5	1027	pbuf_free(p);
mbed714	0:98aadd37a5c5	1028	p = NULL;
mbed714	0:98aadd37a5c5	1029	}
mbed714	0:98aadd37a5c5	1030	}
mbed714	0:98aadd37a5c5	1031	} else {
mbed714	0:98aadd37a5c5	1032	/* referencing the old pbuf is enough */
mbed714	0:98aadd37a5c5	1033	p = q;
mbed714	0:98aadd37a5c5	1034	pbuf_ref(p);
mbed714	0:98aadd37a5c5	1035	}
mbed714	0:98aadd37a5c5	1036	/* packet could be taken over? */
mbed714	0:98aadd37a5c5	1037	if (p != NULL) {
mbed714	0:98aadd37a5c5	1038	/* queue packet ... */
mbed714	0:98aadd37a5c5	1039	struct etharp_q_entry *new_entry;
mbed714	0:98aadd37a5c5	1040	/* allocate a new arp queue entry */
mbed714	0:98aadd37a5c5	1041	new_entry = (struct etharp_q_entry *)memp_malloc(MEMP_ARP_QUEUE);
mbed714	0:98aadd37a5c5	1042	if (new_entry != NULL) {
mbed714	0:98aadd37a5c5	1043	new_entry->next = 0;
mbed714	0:98aadd37a5c5	1044	new_entry->p = p;
mbed714	0:98aadd37a5c5	1045	if(arp_table[i].q != NULL) {
mbed714	0:98aadd37a5c5	1046	/* queue was already existent, append the new entry to the end */
mbed714	0:98aadd37a5c5	1047	struct etharp_q_entry *r;
mbed714	0:98aadd37a5c5	1048	r = arp_table[i].q;
mbed714	0:98aadd37a5c5	1049	while (r->next != NULL) {
mbed714	0:98aadd37a5c5	1050	r = r->next;
mbed714	0:98aadd37a5c5	1051	}
mbed714	0:98aadd37a5c5	1052	r->next = new_entry;
mbed714	0:98aadd37a5c5	1053	} else {
mbed714	0:98aadd37a5c5	1054	/* queue did not exist, first item in queue */
mbed714	0:98aadd37a5c5	1055	arp_table[i].q = new_entry;
mbed714	0:98aadd37a5c5	1056	}
mbed714	0:98aadd37a5c5	1057	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: queued packet %p on ARP entry %"S16_F"\n", (void *)q, (s16_t)i));
mbed714	0:98aadd37a5c5	1058	result = ERR_OK;
mbed714	0:98aadd37a5c5	1059	} else {
mbed714	0:98aadd37a5c5	1060	/* the pool MEMP_ARP_QUEUE is empty */
mbed714	0:98aadd37a5c5	1061	pbuf_free(p);
mbed714	0:98aadd37a5c5	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));
mbed714	0:98aadd37a5c5	1063	/* { result == ERR_MEM } through initialization */
mbed714	0:98aadd37a5c5	1064	}
mbed714	0:98aadd37a5c5	1065	} else {
mbed714	0:98aadd37a5c5	1066	ETHARP_STATS_INC(etharp.memerr);
mbed714	0:98aadd37a5c5	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));
mbed714	0:98aadd37a5c5	1068	/* { result == ERR_MEM } through initialization */
mbed714	0:98aadd37a5c5	1069	}
mbed714	0:98aadd37a5c5	1070	#else /* ARP_QUEUEING */
mbed714	0:98aadd37a5c5	1071	/* q && state == PENDING && ARP_QUEUEING == 0 => result = ERR_MEM */
mbed714	0:98aadd37a5c5	1072	/* { result == ERR_MEM } through initialization */
mbed714	0:98aadd37a5c5	1073	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: Ethernet destination address unknown, queueing disabled, packet %p dropped\n", (void *)q));
mbed714	0:98aadd37a5c5	1074	#endif /* ARP_QUEUEING */
mbed714	0:98aadd37a5c5	1075	}
mbed714	0:98aadd37a5c5	1076	return result;
mbed714	0:98aadd37a5c5	1077	}
mbed714	0:98aadd37a5c5	1078
mbed714	0:98aadd37a5c5	1079	/**
mbed714	0:98aadd37a5c5	1080	* Send a raw ARP packet (opcode and all addresses can be modified)
mbed714	0:98aadd37a5c5	1081	*
mbed714	0:98aadd37a5c5	1082	* @param netif the lwip network interface on which to send the ARP packet
mbed714	0:98aadd37a5c5	1083	* @param ethsrc_addr the source MAC address for the ethernet header
mbed714	0:98aadd37a5c5	1084	* @param ethdst_addr the destination MAC address for the ethernet header
mbed714	0:98aadd37a5c5	1085	* @param hwsrc_addr the source MAC address for the ARP protocol header
mbed714	0:98aadd37a5c5	1086	* @param ipsrc_addr the source IP address for the ARP protocol header
mbed714	0:98aadd37a5c5	1087	* @param hwdst_addr the destination MAC address for the ARP protocol header
mbed714	0:98aadd37a5c5	1088	* @param ipdst_addr the destination IP address for the ARP protocol header
mbed714	0:98aadd37a5c5	1089	* @param opcode the type of the ARP packet
mbed714	0:98aadd37a5c5	1090	* @return ERR_OK if the ARP packet has been sent
mbed714	0:98aadd37a5c5	1091	* ERR_MEM if the ARP packet couldn't be allocated
mbed714	0:98aadd37a5c5	1092	* any other err_t on failure
mbed714	0:98aadd37a5c5	1093	*/
mbed714	0:98aadd37a5c5	1094	#if !LWIP_AUTOIP
mbed714	0:98aadd37a5c5	1095	static
mbed714	0:98aadd37a5c5	1096	#endif /* LWIP_AUTOIP */
mbed714	0:98aadd37a5c5	1097	err_t
mbed714	0:98aadd37a5c5	1098	etharp_raw(struct netif netif, const struct eth_addr ethsrc_addr,
mbed714	0:98aadd37a5c5	1099	const struct eth_addr *ethdst_addr,
mbed714	0:98aadd37a5c5	1100	const struct eth_addr hwsrc_addr, const ip_addr_t ipsrc_addr,
mbed714	0:98aadd37a5c5	1101	const struct eth_addr hwdst_addr, const ip_addr_t ipdst_addr,
mbed714	0:98aadd37a5c5	1102	const u16_t opcode)
mbed714	0:98aadd37a5c5	1103	{
mbed714	0:98aadd37a5c5	1104	struct pbuf *p;
mbed714	0:98aadd37a5c5	1105	err_t result = ERR_OK;
mbed714	0:98aadd37a5c5	1106	struct eth_hdr *ethhdr;
mbed714	0:98aadd37a5c5	1107	struct etharp_hdr *hdr;
mbed714	0:98aadd37a5c5	1108	#if LWIP_AUTOIP
mbed714	0:98aadd37a5c5	1109	const u8_t * ethdst_hwaddr;
mbed714	0:98aadd37a5c5	1110	#endif /* LWIP_AUTOIP */
mbed714	0:98aadd37a5c5	1111
mbed714	0:98aadd37a5c5	1112	/* allocate a pbuf for the outgoing ARP request packet */
mbed714	0:98aadd37a5c5	1113	p = pbuf_alloc(PBUF_RAW, SIZEOF_ETHARP_PACKET, PBUF_RAM);
mbed714	0:98aadd37a5c5	1114	/* could allocate a pbuf for an ARP request? */
mbed714	0:98aadd37a5c5	1115	if (p == NULL) {
mbed714	0:98aadd37a5c5	1116	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_SERIOUS,
mbed714	0:98aadd37a5c5	1117	("etharp_raw: could not allocate pbuf for ARP request.\n"));
mbed714	0:98aadd37a5c5	1118	ETHARP_STATS_INC(etharp.memerr);
mbed714	0:98aadd37a5c5	1119	return ERR_MEM;
mbed714	0:98aadd37a5c5	1120	}
mbed714	0:98aadd37a5c5	1121	LWIP_ASSERT("check that first pbuf can hold struct etharp_hdr",
mbed714	0:98aadd37a5c5	1122	(p->len >= SIZEOF_ETHARP_PACKET));
mbed714	0:98aadd37a5c5	1123
mbed714	0:98aadd37a5c5	1124	ethhdr = (struct eth_hdr *)p->payload;
mbed714	0:98aadd37a5c5	1125	hdr = (struct etharp_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
mbed714	0:98aadd37a5c5	1126	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_raw: sending raw ARP packet.\n"));
mbed714	0:98aadd37a5c5	1127	hdr->opcode = htons(opcode);
mbed714	0:98aadd37a5c5	1128
mbed714	0:98aadd37a5c5	1129	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
mbed714	0:98aadd37a5c5	1130	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
mbed714	0:98aadd37a5c5	1131	#if LWIP_AUTOIP
mbed714	0:98aadd37a5c5	1132	/* If we are using Link-Local, all ARP packets that contain a Link-Local
mbed714	0:98aadd37a5c5	1133	* 'sender IP address' MUST be sent using link-layer broadcast instead of
mbed714	0:98aadd37a5c5	1134	* link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
mbed714	0:98aadd37a5c5	1135	ethdst_hwaddr = ip_addr_islinklocal(ipsrc_addr) ? (u8_t*)(ethbroadcast.addr) : ethdst_addr->addr;
mbed714	0:98aadd37a5c5	1136	#endif /* LWIP_AUTOIP */
mbed714	0:98aadd37a5c5	1137	/* Write the ARP MAC-Addresses */
mbed714	0:98aadd37a5c5	1138	ETHADDR16_COPY(&hdr->shwaddr, hwsrc_addr);
mbed714	0:98aadd37a5c5	1139	ETHADDR16_COPY(&hdr->dhwaddr, hwdst_addr);
mbed714	0:98aadd37a5c5	1140	/* Write the Ethernet MAC-Addresses */
mbed714	0:98aadd37a5c5	1141	#if LWIP_AUTOIP
mbed714	0:98aadd37a5c5	1142	ETHADDR16_COPY(&ethhdr->dest, ethdst_hwaddr);
mbed714	0:98aadd37a5c5	1143	#else /* LWIP_AUTOIP */
mbed714	0:98aadd37a5c5	1144	ETHADDR16_COPY(&ethhdr->dest, ethdst_addr);
mbed714	0:98aadd37a5c5	1145	#endif /* LWIP_AUTOIP */
mbed714	0:98aadd37a5c5	1146	ETHADDR16_COPY(&ethhdr->src, ethsrc_addr);
mbed714	0:98aadd37a5c5	1147	/* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
mbed714	0:98aadd37a5c5	1148	* structure packing. */
mbed714	0:98aadd37a5c5	1149	IPADDR2_COPY(&hdr->sipaddr, ipsrc_addr);
mbed714	0:98aadd37a5c5	1150	IPADDR2_COPY(&hdr->dipaddr, ipdst_addr);
mbed714	0:98aadd37a5c5	1151
mbed714	0:98aadd37a5c5	1152	hdr->hwtype = PP_HTONS(HWTYPE_ETHERNET);
mbed714	0:98aadd37a5c5	1153	hdr->proto = PP_HTONS(ETHTYPE_IP);
mbed714	0:98aadd37a5c5	1154	/* set hwlen and protolen */
mbed714	0:98aadd37a5c5	1155	hdr->hwlen = ETHARP_HWADDR_LEN;
mbed714	0:98aadd37a5c5	1156	hdr->protolen = sizeof(ip_addr_t);
mbed714	0:98aadd37a5c5	1157
mbed714	0:98aadd37a5c5	1158	ethhdr->type = PP_HTONS(ETHTYPE_ARP);
mbed714	0:98aadd37a5c5	1159	/* send ARP query */
mbed714	0:98aadd37a5c5	1160	result = netif->linkoutput(netif, p);
mbed714	0:98aadd37a5c5	1161	ETHARP_STATS_INC(etharp.xmit);
mbed714	0:98aadd37a5c5	1162	/* free ARP query packet */
mbed714	0:98aadd37a5c5	1163	pbuf_free(p);
mbed714	0:98aadd37a5c5	1164	p = NULL;
mbed714	0:98aadd37a5c5	1165	/* could not allocate pbuf for ARP request */
mbed714	0:98aadd37a5c5	1166
mbed714	0:98aadd37a5c5	1167	return result;
mbed714	0:98aadd37a5c5	1168	}
mbed714	0:98aadd37a5c5	1169
mbed714	0:98aadd37a5c5	1170	/**
mbed714	0:98aadd37a5c5	1171	* Send an ARP request packet asking for ipaddr.
mbed714	0:98aadd37a5c5	1172	*
mbed714	0:98aadd37a5c5	1173	* @param netif the lwip network interface on which to send the request
mbed714	0:98aadd37a5c5	1174	* @param ipaddr the IP address for which to ask
mbed714	0:98aadd37a5c5	1175	* @return ERR_OK if the request has been sent
mbed714	0:98aadd37a5c5	1176	* ERR_MEM if the ARP packet couldn't be allocated
mbed714	0:98aadd37a5c5	1177	* any other err_t on failure
mbed714	0:98aadd37a5c5	1178	*/
mbed714	0:98aadd37a5c5	1179	err_t
mbed714	0:98aadd37a5c5	1180	etharp_request(struct netif netif, ip_addr_t ipaddr)
mbed714	0:98aadd37a5c5	1181	{
mbed714	0:98aadd37a5c5	1182	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_request: sending ARP request.\n"));
mbed714	0:98aadd37a5c5	1183	return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, &ethbroadcast,
mbed714	0:98aadd37a5c5	1184	(struct eth_addr *)netif->hwaddr, &netif->ip_addr, &ethzero,
mbed714	0:98aadd37a5c5	1185	ipaddr, ARP_REQUEST);
mbed714	0:98aadd37a5c5	1186	}
mbed714	0:98aadd37a5c5	1187	#endif /* LWIP_ARP */
mbed714	0:98aadd37a5c5	1188
mbed714	0:98aadd37a5c5	1189	/**
mbed714	0:98aadd37a5c5	1190	* Process received ethernet frames. Using this function instead of directly
mbed714	0:98aadd37a5c5	1191	* calling ip_input and passing ARP frames through etharp in ethernetif_input,
mbed714	0:98aadd37a5c5	1192	* the ARP cache is protected from concurrent access.
mbed714	0:98aadd37a5c5	1193	*
mbed714	0:98aadd37a5c5	1194	* @param p the recevied packet, p->payload pointing to the ethernet header
mbed714	0:98aadd37a5c5	1195	* @param netif the network interface on which the packet was received
mbed714	0:98aadd37a5c5	1196	*/
mbed714	0:98aadd37a5c5	1197	err_t
mbed714	0:98aadd37a5c5	1198	ethernet_input(struct pbuf p, struct netif netif)
mbed714	0:98aadd37a5c5	1199	{
mbed714	0:98aadd37a5c5	1200	struct eth_hdr* ethhdr;
mbed714	0:98aadd37a5c5	1201	u16_t type;
mbed714	0:98aadd37a5c5	1202
mbed714	0:98aadd37a5c5	1203	/* points to packet payload, which starts with an Ethernet header */
mbed714	0:98aadd37a5c5	1204	ethhdr = (struct eth_hdr *)p->payload;
mbed714	0:98aadd37a5c5	1205	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE,
mbed714	0:98aadd37a5c5	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",
mbed714	0:98aadd37a5c5	1207	(unsigned)ethhdr->dest.addr[0], (unsigned)ethhdr->dest.addr[1], (unsigned)ethhdr->dest.addr[2],
mbed714	0:98aadd37a5c5	1208	(unsigned)ethhdr->dest.addr[3], (unsigned)ethhdr->dest.addr[4], (unsigned)ethhdr->dest.addr[5],
mbed714	0:98aadd37a5c5	1209	(unsigned)ethhdr->src.addr[0], (unsigned)ethhdr->src.addr[1], (unsigned)ethhdr->src.addr[2],
mbed714	0:98aadd37a5c5	1210	(unsigned)ethhdr->src.addr[3], (unsigned)ethhdr->src.addr[4], (unsigned)ethhdr->src.addr[5],
mbed714	0:98aadd37a5c5	1211	(unsigned)htons(ethhdr->type)));
mbed714	0:98aadd37a5c5	1212
mbed714	0:98aadd37a5c5	1213	type = ethhdr->type;
mbed714	0:98aadd37a5c5	1214	#if ETHARP_SUPPORT_VLAN
mbed714	0:98aadd37a5c5	1215	if (type == PP_HTONS(ETHTYPE_VLAN)) {
mbed714	0:98aadd37a5c5	1216	struct eth_vlan_hdr vlan = (struct eth_vlan_hdr)(((char*)ethhdr) + SIZEOF_ETH_HDR);
mbed714	0:98aadd37a5c5	1217	#ifdef ETHARP_VLAN_CHECK /* if not, allow all VLANs */
mbed714	0:98aadd37a5c5	1218	if (VLAN_ID(vlan) != ETHARP_VLAN_CHECK) {
mbed714	0:98aadd37a5c5	1219	/* silently ignore this packet: not for our VLAN */
mbed714	0:98aadd37a5c5	1220	pbuf_free(p);
mbed714	0:98aadd37a5c5	1221	return ERR_OK;
mbed714	0:98aadd37a5c5	1222	}
mbed714	0:98aadd37a5c5	1223	#endif /* ETHARP_VLAN_CHECK */
mbed714	0:98aadd37a5c5	1224	type = vlan->tpid;
mbed714	0:98aadd37a5c5	1225	}
mbed714	0:98aadd37a5c5	1226	#endif /* ETHARP_SUPPORT_VLAN */
mbed714	0:98aadd37a5c5	1227
mbed714	0:98aadd37a5c5	1228	#if LWIP_ARP_FILTER_NETIF
mbed714	0:98aadd37a5c5	1229	netif = LWIP_ARP_FILTER_NETIF_FN(p, netif, htons(type));
mbed714	0:98aadd37a5c5	1230	#endif /* LWIP_ARP_FILTER_NETIF*/
mbed714	0:98aadd37a5c5	1231
mbed714	0:98aadd37a5c5	1232	switch (type) {
mbed714	0:98aadd37a5c5	1233	#if LWIP_ARP
mbed714	0:98aadd37a5c5	1234	/* IP packet? */
mbed714	0:98aadd37a5c5	1235	case PP_HTONS(ETHTYPE_IP):
mbed714	0:98aadd37a5c5	1236	if (!(netif->flags & NETIF_FLAG_ETHARP)) {
mbed714	0:98aadd37a5c5	1237	goto free_and_return;
mbed714	0:98aadd37a5c5	1238	}
mbed714	0:98aadd37a5c5	1239	#if ETHARP_TRUST_IP_MAC
mbed714	0:98aadd37a5c5	1240	/* update ARP table */
mbed714	0:98aadd37a5c5	1241	etharp_ip_input(netif, p);
mbed714	0:98aadd37a5c5	1242	#endif /* ETHARP_TRUST_IP_MAC */
mbed714	0:98aadd37a5c5	1243	/* skip Ethernet header */
mbed714	0:98aadd37a5c5	1244	if(pbuf_header(p, -(s16_t)SIZEOF_ETH_HDR)) {
mbed714	0:98aadd37a5c5	1245	LWIP_ASSERT("Can't move over header in packet", 0);
mbed714	0:98aadd37a5c5	1246	goto free_and_return;
mbed714	0:98aadd37a5c5	1247	} else {
mbed714	0:98aadd37a5c5	1248	/* pass to IP layer */
mbed714	0:98aadd37a5c5	1249	ip_input(p, netif);
mbed714	0:98aadd37a5c5	1250	}
mbed714	0:98aadd37a5c5	1251	break;
mbed714	0:98aadd37a5c5	1252
mbed714	0:98aadd37a5c5	1253	case PP_HTONS(ETHTYPE_ARP):
mbed714	0:98aadd37a5c5	1254	if (!(netif->flags & NETIF_FLAG_ETHARP)) {
mbed714	0:98aadd37a5c5	1255	goto free_and_return;
mbed714	0:98aadd37a5c5	1256	}
mbed714	0:98aadd37a5c5	1257	/* pass p to ARP module */
mbed714	0:98aadd37a5c5	1258	etharp_arp_input(netif, (struct eth_addr*)(netif->hwaddr), p);
mbed714	0:98aadd37a5c5	1259	break;
mbed714	0:98aadd37a5c5	1260	#endif /* LWIP_ARP */
mbed714	0:98aadd37a5c5	1261	#if PPPOE_SUPPORT
mbed714	0:98aadd37a5c5	1262	case PP_HTONS(ETHTYPE_PPPOEDISC): /* PPP Over Ethernet Discovery Stage */
mbed714	0:98aadd37a5c5	1263	pppoe_disc_input(netif, p);
mbed714	0:98aadd37a5c5	1264	break;
mbed714	0:98aadd37a5c5	1265
mbed714	0:98aadd37a5c5	1266	case PP_HTONS(ETHTYPE_PPPOE): /* PPP Over Ethernet Session Stage */
mbed714	0:98aadd37a5c5	1267	pppoe_data_input(netif, p);
mbed714	0:98aadd37a5c5	1268	break;
mbed714	0:98aadd37a5c5	1269	#endif /* PPPOE_SUPPORT */
mbed714	0:98aadd37a5c5	1270
mbed714	0:98aadd37a5c5	1271	default:
mbed714	0:98aadd37a5c5	1272	ETHARP_STATS_INC(etharp.proterr);
mbed714	0:98aadd37a5c5	1273	ETHARP_STATS_INC(etharp.drop);
mbed714	0:98aadd37a5c5	1274	goto free_and_return;
mbed714	0:98aadd37a5c5	1275	}
mbed714	0:98aadd37a5c5	1276
mbed714	0:98aadd37a5c5	1277	/* This means the pbuf is freed or consumed,
mbed714	0:98aadd37a5c5	1278	so the caller doesn't have to free it again */
mbed714	0:98aadd37a5c5	1279	return ERR_OK;
mbed714	0:98aadd37a5c5	1280
mbed714	0:98aadd37a5c5	1281	free_and_return:
mbed714	0:98aadd37a5c5	1282	pbuf_free(p);
mbed714	0:98aadd37a5c5	1283	return ERR_OK;
mbed714	0:98aadd37a5c5	1284	}
mbed714	0:98aadd37a5c5	1285	#endif /* LWIP_ARP \|\| LWIP_ETHERNET */

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Type:	Library
Created:	29 Sep 2010
Imports:	7
Forks:	0
Commits:	4
Dependents:	0
Dependencies:	0
Followers:	1

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lwip/netif/etharp.c@3:0c324737064d, 2010-11-09 (annotated)

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