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Embedded WebSockets Experiment

Core/lwIP/netif/etharp.c@0:6dee052a3fa4, 2011-07-26 (annotated)

Committer:: nandgate
Date:: Tue Jul 26 05:30:53 2011 +0000
Revision:: 0:6dee052a3fa4

Who changed what in which revision?

User	Revision	Line number	New contents of line
nandgate	0:6dee052a3fa4	1	/**
nandgate	0:6dee052a3fa4	2	* @file
nandgate	0:6dee052a3fa4	3	* Address Resolution Protocol module for IP over Ethernet
nandgate	0:6dee052a3fa4	4	*
nandgate	0:6dee052a3fa4	5	* Functionally, ARP is divided into two parts. The first maps an IP address
nandgate	0:6dee052a3fa4	6	* to a physical address when sending a packet, and the second part answers
nandgate	0:6dee052a3fa4	7	* requests from other machines for our physical address.
nandgate	0:6dee052a3fa4	8	*
nandgate	0:6dee052a3fa4	9	* This implementation complies with RFC 826 (Ethernet ARP). It supports
nandgate	0:6dee052a3fa4	10	* Gratuitious ARP from RFC3220 (IP Mobility Support for IPv4) section 4.6
nandgate	0:6dee052a3fa4	11	* if an interface calls etharp_gratuitous(our_netif) upon address change.
nandgate	0:6dee052a3fa4	12	*/
nandgate	0:6dee052a3fa4	13
nandgate	0:6dee052a3fa4	14	/*
nandgate	0:6dee052a3fa4	15	* Copyright (c) 2001-2003 Swedish Institute of Computer Science.
nandgate	0:6dee052a3fa4	16	* Copyright (c) 2003-2004 Leon Woestenberg <leon.woestenberg@axon.tv>
nandgate	0:6dee052a3fa4	17	* Copyright (c) 2003-2004 Axon Digital Design B.V., The Netherlands.
nandgate	0:6dee052a3fa4	18	* All rights reserved.
nandgate	0:6dee052a3fa4	19	*
nandgate	0:6dee052a3fa4	20	* Redistribution and use in source and binary forms, with or without modification,
nandgate	0:6dee052a3fa4	21	* are permitted provided that the following conditions are met:
nandgate	0:6dee052a3fa4	22	*
nandgate	0:6dee052a3fa4	23	* 1. Redistributions of source code must retain the above copyright notice,
nandgate	0:6dee052a3fa4	24	* this list of conditions and the following disclaimer.
nandgate	0:6dee052a3fa4	25	* 2. Redistributions in binary form must reproduce the above copyright notice,
nandgate	0:6dee052a3fa4	26	* this list of conditions and the following disclaimer in the documentation
nandgate	0:6dee052a3fa4	27	* and/or other materials provided with the distribution.
nandgate	0:6dee052a3fa4	28	* 3. The name of the author may not be used to endorse or promote products
nandgate	0:6dee052a3fa4	29	* derived from this software without specific prior written permission.
nandgate	0:6dee052a3fa4	30	*
nandgate	0:6dee052a3fa4	31	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
nandgate	0:6dee052a3fa4	32	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
nandgate	0:6dee052a3fa4	33	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
nandgate	0:6dee052a3fa4	34	* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
nandgate	0:6dee052a3fa4	35	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
nandgate	0:6dee052a3fa4	36	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
nandgate	0:6dee052a3fa4	37	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
nandgate	0:6dee052a3fa4	38	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
nandgate	0:6dee052a3fa4	39	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
nandgate	0:6dee052a3fa4	40	* OF SUCH DAMAGE.
nandgate	0:6dee052a3fa4	41	*
nandgate	0:6dee052a3fa4	42	* This file is part of the lwIP TCP/IP stack.
nandgate	0:6dee052a3fa4	43	*
nandgate	0:6dee052a3fa4	44	*/
nandgate	0:6dee052a3fa4	45
nandgate	0:6dee052a3fa4	46	#include "lwip/opt.h"
nandgate	0:6dee052a3fa4	47
nandgate	0:6dee052a3fa4	48	#if LWIP_ARP /* don't build if not configured for use in lwipopts.h */
nandgate	0:6dee052a3fa4	49
nandgate	0:6dee052a3fa4	50	#include "lwip/inet.h"
nandgate	0:6dee052a3fa4	51	#include "lwip/ip.h"
nandgate	0:6dee052a3fa4	52	#include "lwip/stats.h"
nandgate	0:6dee052a3fa4	53	#include "lwip/snmp.h"
nandgate	0:6dee052a3fa4	54	#include "lwip/dhcp.h"
nandgate	0:6dee052a3fa4	55	#include "lwip/autoip.h"
nandgate	0:6dee052a3fa4	56	#include "netif/etharp.h"
nandgate	0:6dee052a3fa4	57
nandgate	0:6dee052a3fa4	58	#if PPPOE_SUPPORT
nandgate	0:6dee052a3fa4	59	#include "netif/ppp_oe.h"
nandgate	0:6dee052a3fa4	60	#endif /* PPPOE_SUPPORT */
nandgate	0:6dee052a3fa4	61
nandgate	0:6dee052a3fa4	62	#include <string.h>
nandgate	0:6dee052a3fa4	63
nandgate	0:6dee052a3fa4	64	/** the time an ARP entry stays valid after its last update,
nandgate	0:6dee052a3fa4	65	* for ARP_TMR_INTERVAL = 5000, this is
nandgate	0:6dee052a3fa4	66	* (240 * 5) seconds = 20 minutes.
nandgate	0:6dee052a3fa4	67	*/
nandgate	0:6dee052a3fa4	68	#define ARP_MAXAGE 240
nandgate	0:6dee052a3fa4	69	/** the time an ARP entry stays pending after first request,
nandgate	0:6dee052a3fa4	70	* for ARP_TMR_INTERVAL = 5000, this is
nandgate	0:6dee052a3fa4	71	* (2 * 5) seconds = 10 seconds.
nandgate	0:6dee052a3fa4	72	*
nandgate	0:6dee052a3fa4	73	* @internal Keep this number at least 2, otherwise it might
nandgate	0:6dee052a3fa4	74	* run out instantly if the timeout occurs directly after a request.
nandgate	0:6dee052a3fa4	75	*/
nandgate	0:6dee052a3fa4	76	#define ARP_MAXPENDING 2
nandgate	0:6dee052a3fa4	77
nandgate	0:6dee052a3fa4	78	#define HWTYPE_ETHERNET 1
nandgate	0:6dee052a3fa4	79
nandgate	0:6dee052a3fa4	80	#define ARPH_HWLEN(hdr) (ntohs((hdr)->_hwlen_protolen) >> 8)
nandgate	0:6dee052a3fa4	81	#define ARPH_PROTOLEN(hdr) (ntohs((hdr)->_hwlen_protolen) & 0xff)
nandgate	0:6dee052a3fa4	82
nandgate	0:6dee052a3fa4	83	#define ARPH_HWLEN_SET(hdr, len) (hdr)->_hwlen_protolen = htons(ARPH_PROTOLEN(hdr) \| ((len) << 8))
nandgate	0:6dee052a3fa4	84	#define ARPH_PROTOLEN_SET(hdr, len) (hdr)->_hwlen_protolen = htons((len) \| (ARPH_HWLEN(hdr) << 8))
nandgate	0:6dee052a3fa4	85
nandgate	0:6dee052a3fa4	86	enum etharp_state {
nandgate	0:6dee052a3fa4	87	ETHARP_STATE_EMPTY = 0,
nandgate	0:6dee052a3fa4	88	ETHARP_STATE_PENDING,
nandgate	0:6dee052a3fa4	89	ETHARP_STATE_STABLE
nandgate	0:6dee052a3fa4	90	};
nandgate	0:6dee052a3fa4	91
nandgate	0:6dee052a3fa4	92	struct etharp_entry {
nandgate	0:6dee052a3fa4	93	#if ARP_QUEUEING
nandgate	0:6dee052a3fa4	94	/**
nandgate	0:6dee052a3fa4	95	* Pointer to queue of pending outgoing packets on this ARP entry.
nandgate	0:6dee052a3fa4	96	*/
nandgate	0:6dee052a3fa4	97	struct etharp_q_entry *q;
nandgate	0:6dee052a3fa4	98	#endif
nandgate	0:6dee052a3fa4	99	struct ip_addr ipaddr;
nandgate	0:6dee052a3fa4	100	struct eth_addr ethaddr;
nandgate	0:6dee052a3fa4	101	enum etharp_state state;
nandgate	0:6dee052a3fa4	102	u8_t ctime;
nandgate	0:6dee052a3fa4	103	struct netif *netif;
nandgate	0:6dee052a3fa4	104	};
nandgate	0:6dee052a3fa4	105
nandgate	0:6dee052a3fa4	106	const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}};
nandgate	0:6dee052a3fa4	107	const struct eth_addr ethzero = {{0,0,0,0,0,0}};
nandgate	0:6dee052a3fa4	108	static struct etharp_entry arp_table[ARP_TABLE_SIZE] MEM_POSITION;
nandgate	0:6dee052a3fa4	109	#if !LWIP_NETIF_HWADDRHINT
nandgate	0:6dee052a3fa4	110	static u8_t etharp_cached_entry MEM_POSITION;
nandgate	0:6dee052a3fa4	111	#endif
nandgate	0:6dee052a3fa4	112
nandgate	0:6dee052a3fa4	113	/**
nandgate	0:6dee052a3fa4	114	* Try hard to create a new entry - we want the IP address to appear in
nandgate	0:6dee052a3fa4	115	* the cache (even if this means removing an active entry or so). */
nandgate	0:6dee052a3fa4	116	#define ETHARP_TRY_HARD 1
nandgate	0:6dee052a3fa4	117	#define ETHARP_FIND_ONLY 2
nandgate	0:6dee052a3fa4	118
nandgate	0:6dee052a3fa4	119	#if LWIP_NETIF_HWADDRHINT
nandgate	0:6dee052a3fa4	120	#define NETIF_SET_HINT(netif, hint) if (((netif) != NULL) && ((netif)->addr_hint != NULL)) \
nandgate	0:6dee052a3fa4	121	*((netif)->addr_hint) = (hint);
nandgate	0:6dee052a3fa4	122	static s8_t find_entry(struct ip_addr ipaddr, u8_t flags, struct netif netif);
nandgate	0:6dee052a3fa4	123	#else /* LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	124	static s8_t find_entry(struct ip_addr *ipaddr, u8_t flags);
nandgate	0:6dee052a3fa4	125	#endif /* LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	126
nandgate	0:6dee052a3fa4	127	static err_t update_arp_entry(struct netif netif, struct ip_addr ipaddr, struct eth_addr *ethaddr, u8_t flags);
nandgate	0:6dee052a3fa4	128
nandgate	0:6dee052a3fa4	129
nandgate	0:6dee052a3fa4	130	/* Some checks, instead of etharp_init(): */
nandgate	0:6dee052a3fa4	131	#if (LWIP_ARP && (ARP_TABLE_SIZE > 0x7f))
nandgate	0:6dee052a3fa4	132	#error "If you want to use ARP, ARP_TABLE_SIZE must fit in an s8_t, so, you have to reduce it in your lwipopts.h"
nandgate	0:6dee052a3fa4	133	#endif
nandgate	0:6dee052a3fa4	134
nandgate	0:6dee052a3fa4	135
nandgate	0:6dee052a3fa4	136	#if ARP_QUEUEING
nandgate	0:6dee052a3fa4	137	/**
nandgate	0:6dee052a3fa4	138	* Free a complete queue of etharp entries
nandgate	0:6dee052a3fa4	139	*
nandgate	0:6dee052a3fa4	140	* @param q a qeueue of etharp_q_entry's to free
nandgate	0:6dee052a3fa4	141	*/
nandgate	0:6dee052a3fa4	142	static void
nandgate	0:6dee052a3fa4	143	free_etharp_q(struct etharp_q_entry *q)
nandgate	0:6dee052a3fa4	144	{
nandgate	0:6dee052a3fa4	145	struct etharp_q_entry *r;
nandgate	0:6dee052a3fa4	146	LWIP_ASSERT("q != NULL", q != NULL);
nandgate	0:6dee052a3fa4	147	LWIP_ASSERT("q->p != NULL", q->p != NULL);
nandgate	0:6dee052a3fa4	148	while (q) {
nandgate	0:6dee052a3fa4	149	r = q;
nandgate	0:6dee052a3fa4	150	q = q->next;
nandgate	0:6dee052a3fa4	151	LWIP_ASSERT("r->p != NULL", (r->p != NULL));
nandgate	0:6dee052a3fa4	152	pbuf_free(r->p);
nandgate	0:6dee052a3fa4	153	memp_free(MEMP_ARP_QUEUE, r);
nandgate	0:6dee052a3fa4	154	}
nandgate	0:6dee052a3fa4	155	}
nandgate	0:6dee052a3fa4	156	#endif
nandgate	0:6dee052a3fa4	157
nandgate	0:6dee052a3fa4	158	/**
nandgate	0:6dee052a3fa4	159	* Clears expired entries in the ARP table.
nandgate	0:6dee052a3fa4	160	*
nandgate	0:6dee052a3fa4	161	* This function should be called every ETHARP_TMR_INTERVAL microseconds (5 seconds),
nandgate	0:6dee052a3fa4	162	* in order to expire entries in the ARP table.
nandgate	0:6dee052a3fa4	163	*/
nandgate	0:6dee052a3fa4	164	void
nandgate	0:6dee052a3fa4	165	etharp_tmr(void)
nandgate	0:6dee052a3fa4	166	{
nandgate	0:6dee052a3fa4	167	u8_t i;
nandgate	0:6dee052a3fa4	168
nandgate	0:6dee052a3fa4	169	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer\n"));
nandgate	0:6dee052a3fa4	170	/* remove expired entries from the ARP table */
nandgate	0:6dee052a3fa4	171	for (i = 0; i < ARP_TABLE_SIZE; ++i) {
nandgate	0:6dee052a3fa4	172	arp_table[i].ctime++;
nandgate	0:6dee052a3fa4	173	if (((arp_table[i].state == ETHARP_STATE_STABLE) &&
nandgate	0:6dee052a3fa4	174	(arp_table[i].ctime >= ARP_MAXAGE)) \|\|
nandgate	0:6dee052a3fa4	175	((arp_table[i].state == ETHARP_STATE_PENDING) &&
nandgate	0:6dee052a3fa4	176	(arp_table[i].ctime >= ARP_MAXPENDING))) {
nandgate	0:6dee052a3fa4	177	/* pending or stable entry has become old! */
nandgate	0:6dee052a3fa4	178	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: expired %s entry %"U16_F".\n",
nandgate	0:6dee052a3fa4	179	arp_table[i].state == ETHARP_STATE_STABLE ? "stable" : "pending", (u16_t)i));
nandgate	0:6dee052a3fa4	180	/* clean up entries that have just been expired */
nandgate	0:6dee052a3fa4	181	/* remove from SNMP ARP index tree */
nandgate	0:6dee052a3fa4	182	snmp_delete_arpidx_tree(arp_table[i].netif, &arp_table[i].ipaddr);
nandgate	0:6dee052a3fa4	183	#if ARP_QUEUEING
nandgate	0:6dee052a3fa4	184	/* and empty packet queue */
nandgate	0:6dee052a3fa4	185	if (arp_table[i].q != NULL) {
nandgate	0:6dee052a3fa4	186	/* remove all queued packets */
nandgate	0:6dee052a3fa4	187	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: freeing entry %"U16_F", packet queue %p.\n", (u16_t)i, (void *)(arp_table[i].q)));
nandgate	0:6dee052a3fa4	188	free_etharp_q(arp_table[i].q);
nandgate	0:6dee052a3fa4	189	arp_table[i].q = NULL;
nandgate	0:6dee052a3fa4	190	}
nandgate	0:6dee052a3fa4	191	#endif
nandgate	0:6dee052a3fa4	192	/* recycle entry for re-use */
nandgate	0:6dee052a3fa4	193	arp_table[i].state = ETHARP_STATE_EMPTY;
nandgate	0:6dee052a3fa4	194	}
nandgate	0:6dee052a3fa4	195	#if ARP_QUEUEING
nandgate	0:6dee052a3fa4	196	/* still pending entry? (not expired) */
nandgate	0:6dee052a3fa4	197	if (arp_table[i].state == ETHARP_STATE_PENDING) {
nandgate	0:6dee052a3fa4	198	/* resend an ARP query here? */
nandgate	0:6dee052a3fa4	199	}
nandgate	0:6dee052a3fa4	200	#endif
nandgate	0:6dee052a3fa4	201	}
nandgate	0:6dee052a3fa4	202	}
nandgate	0:6dee052a3fa4	203
nandgate	0:6dee052a3fa4	204	/**
nandgate	0:6dee052a3fa4	205	* Search the ARP table for a matching or new entry.
nandgate	0:6dee052a3fa4	206	*
nandgate	0:6dee052a3fa4	207	* If an IP address is given, return a pending or stable ARP entry that matches
nandgate	0:6dee052a3fa4	208	* the address. If no match is found, create a new entry with this address set,
nandgate	0:6dee052a3fa4	209	* but in state ETHARP_EMPTY. The caller must check and possibly change the
nandgate	0:6dee052a3fa4	210	* state of the returned entry.
nandgate	0:6dee052a3fa4	211	*
nandgate	0:6dee052a3fa4	212	* If ipaddr is NULL, return a initialized new entry in state ETHARP_EMPTY.
nandgate	0:6dee052a3fa4	213	*
nandgate	0:6dee052a3fa4	214	* In all cases, attempt to create new entries from an empty entry. If no
nandgate	0:6dee052a3fa4	215	* empty entries are available and ETHARP_TRY_HARD flag is set, recycle
nandgate	0:6dee052a3fa4	216	* old entries. Heuristic choose the least important entry for recycling.
nandgate	0:6dee052a3fa4	217	*
nandgate	0:6dee052a3fa4	218	* @param ipaddr IP address to find in ARP cache, or to add if not found.
nandgate	0:6dee052a3fa4	219	* @param flags
nandgate	0:6dee052a3fa4	220	* - ETHARP_TRY_HARD: Try hard to create a entry by allowing recycling of
nandgate	0:6dee052a3fa4	221	* active (stable or pending) entries.
nandgate	0:6dee052a3fa4	222	*
nandgate	0:6dee052a3fa4	223	* @return The ARP entry index that matched or is created, ERR_MEM if no
nandgate	0:6dee052a3fa4	224	* entry is found or could be recycled.
nandgate	0:6dee052a3fa4	225	*/
nandgate	0:6dee052a3fa4	226	static s8_t
nandgate	0:6dee052a3fa4	227	#if LWIP_NETIF_HWADDRHINT
nandgate	0:6dee052a3fa4	228	find_entry(struct ip_addr ipaddr, u8_t flags, struct netif netif)
nandgate	0:6dee052a3fa4	229	#else /* LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	230	find_entry(struct ip_addr *ipaddr, u8_t flags)
nandgate	0:6dee052a3fa4	231	#endif /* LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	232	{
nandgate	0:6dee052a3fa4	233	s8_t old_pending = ARP_TABLE_SIZE, old_stable = ARP_TABLE_SIZE;
nandgate	0:6dee052a3fa4	234	s8_t empty = ARP_TABLE_SIZE;
nandgate	0:6dee052a3fa4	235	u8_t i = 0, age_pending = 0, age_stable = 0;
nandgate	0:6dee052a3fa4	236	#if ARP_QUEUEING
nandgate	0:6dee052a3fa4	237	/* oldest entry with packets on queue */
nandgate	0:6dee052a3fa4	238	s8_t old_queue = ARP_TABLE_SIZE;
nandgate	0:6dee052a3fa4	239	/* its age */
nandgate	0:6dee052a3fa4	240	u8_t age_queue = 0;
nandgate	0:6dee052a3fa4	241	#endif
nandgate	0:6dee052a3fa4	242
nandgate	0:6dee052a3fa4	243	/* First, test if the last call to this function asked for the
nandgate	0:6dee052a3fa4	244	* same address. If so, we're really fast! */
nandgate	0:6dee052a3fa4	245	if (ipaddr) {
nandgate	0:6dee052a3fa4	246	/* ipaddr to search for was given */
nandgate	0:6dee052a3fa4	247	#if LWIP_NETIF_HWADDRHINT
nandgate	0:6dee052a3fa4	248	if ((netif != NULL) && (netif->addr_hint != NULL)) {
nandgate	0:6dee052a3fa4	249	/* per-pcb cached entry was given */
nandgate	0:6dee052a3fa4	250	u8_t per_pcb_cache = *(netif->addr_hint);
nandgate	0:6dee052a3fa4	251	if ((per_pcb_cache < ARP_TABLE_SIZE) && arp_table[per_pcb_cache].state == ETHARP_STATE_STABLE) {
nandgate	0:6dee052a3fa4	252	/* the per-pcb-cached entry is stable */
nandgate	0:6dee052a3fa4	253	if (ip_addr_cmp(ipaddr, &arp_table[per_pcb_cache].ipaddr)) {
nandgate	0:6dee052a3fa4	254	/* per-pcb cached entry was the right one! */
nandgate	0:6dee052a3fa4	255	ETHARP_STATS_INC(etharp.cachehit);
nandgate	0:6dee052a3fa4	256	return per_pcb_cache;
nandgate	0:6dee052a3fa4	257	}
nandgate	0:6dee052a3fa4	258	}
nandgate	0:6dee052a3fa4	259	}
nandgate	0:6dee052a3fa4	260	#else /* #if LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	261	if (arp_table[etharp_cached_entry].state == ETHARP_STATE_STABLE) {
nandgate	0:6dee052a3fa4	262	/* the cached entry is stable */
nandgate	0:6dee052a3fa4	263	if (ip_addr_cmp(ipaddr, &arp_table[etharp_cached_entry].ipaddr)) {
nandgate	0:6dee052a3fa4	264	/* cached entry was the right one! */
nandgate	0:6dee052a3fa4	265	ETHARP_STATS_INC(etharp.cachehit);
nandgate	0:6dee052a3fa4	266	return etharp_cached_entry;
nandgate	0:6dee052a3fa4	267	}
nandgate	0:6dee052a3fa4	268	}
nandgate	0:6dee052a3fa4	269	#endif /* #if LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	270	}
nandgate	0:6dee052a3fa4	271
nandgate	0:6dee052a3fa4	272	/**
nandgate	0:6dee052a3fa4	273	* a) do a search through the cache, remember candidates
nandgate	0:6dee052a3fa4	274	* b) select candidate entry
nandgate	0:6dee052a3fa4	275	* c) create new entry
nandgate	0:6dee052a3fa4	276	*/
nandgate	0:6dee052a3fa4	277
nandgate	0:6dee052a3fa4	278	/* a) in a single search sweep, do all of this
nandgate	0:6dee052a3fa4	279	* 1) remember the first empty entry (if any)
nandgate	0:6dee052a3fa4	280	* 2) remember the oldest stable entry (if any)
nandgate	0:6dee052a3fa4	281	* 3) remember the oldest pending entry without queued packets (if any)
nandgate	0:6dee052a3fa4	282	* 4) remember the oldest pending entry with queued packets (if any)
nandgate	0:6dee052a3fa4	283	* 5) search for a matching IP entry, either pending or stable
nandgate	0:6dee052a3fa4	284	* until 5 matches, or all entries are searched for.
nandgate	0:6dee052a3fa4	285	*/
nandgate	0:6dee052a3fa4	286
nandgate	0:6dee052a3fa4	287	for (i = 0; i < ARP_TABLE_SIZE; ++i) {
nandgate	0:6dee052a3fa4	288	/* no empty entry found yet and now we do find one? */
nandgate	0:6dee052a3fa4	289	if ((empty == ARP_TABLE_SIZE) && (arp_table[i].state == ETHARP_STATE_EMPTY)) {
nandgate	0:6dee052a3fa4	290	LWIP_DEBUGF(ETHARP_DEBUG, ("find_entry: found empty entry %"U16_F"\n", (u16_t)i));
nandgate	0:6dee052a3fa4	291	/* remember first empty entry */
nandgate	0:6dee052a3fa4	292	empty = i;
nandgate	0:6dee052a3fa4	293	}
nandgate	0:6dee052a3fa4	294	/* pending entry? */
nandgate	0:6dee052a3fa4	295	else if (arp_table[i].state == ETHARP_STATE_PENDING) {
nandgate	0:6dee052a3fa4	296	/* if given, does IP address match IP address in ARP entry? */
nandgate	0:6dee052a3fa4	297	if (ipaddr && ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
nandgate	0:6dee052a3fa4	298	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: found matching pending entry %"U16_F"\n", (u16_t)i));
nandgate	0:6dee052a3fa4	299	/* found exact IP address match, simply bail out */
nandgate	0:6dee052a3fa4	300	#if LWIP_NETIF_HWADDRHINT
nandgate	0:6dee052a3fa4	301	NETIF_SET_HINT(netif, i);
nandgate	0:6dee052a3fa4	302	#else /* #if LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	303	etharp_cached_entry = i;
nandgate	0:6dee052a3fa4	304	#endif /* #if LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	305	return i;
nandgate	0:6dee052a3fa4	306	#if ARP_QUEUEING
nandgate	0:6dee052a3fa4	307	/* pending with queued packets? */
nandgate	0:6dee052a3fa4	308	} else if (arp_table[i].q != NULL) {
nandgate	0:6dee052a3fa4	309	if (arp_table[i].ctime >= age_queue) {
nandgate	0:6dee052a3fa4	310	old_queue = i;
nandgate	0:6dee052a3fa4	311	age_queue = arp_table[i].ctime;
nandgate	0:6dee052a3fa4	312	}
nandgate	0:6dee052a3fa4	313	#endif
nandgate	0:6dee052a3fa4	314	/* pending without queued packets? */
nandgate	0:6dee052a3fa4	315	} else {
nandgate	0:6dee052a3fa4	316	if (arp_table[i].ctime >= age_pending) {
nandgate	0:6dee052a3fa4	317	old_pending = i;
nandgate	0:6dee052a3fa4	318	age_pending = arp_table[i].ctime;
nandgate	0:6dee052a3fa4	319	}
nandgate	0:6dee052a3fa4	320	}
nandgate	0:6dee052a3fa4	321	}
nandgate	0:6dee052a3fa4	322	/* stable entry? */
nandgate	0:6dee052a3fa4	323	else if (arp_table[i].state == ETHARP_STATE_STABLE) {
nandgate	0:6dee052a3fa4	324	/* if given, does IP address match IP address in ARP entry? */
nandgate	0:6dee052a3fa4	325	if (ipaddr && ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
nandgate	0:6dee052a3fa4	326	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: found matching stable entry %"U16_F"\n", (u16_t)i));
nandgate	0:6dee052a3fa4	327	/* found exact IP address match, simply bail out */
nandgate	0:6dee052a3fa4	328	#if LWIP_NETIF_HWADDRHINT
nandgate	0:6dee052a3fa4	329	NETIF_SET_HINT(netif, i);
nandgate	0:6dee052a3fa4	330	#else /* #if LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	331	etharp_cached_entry = i;
nandgate	0:6dee052a3fa4	332	#endif /* #if LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	333	return i;
nandgate	0:6dee052a3fa4	334	/* remember entry with oldest stable entry in oldest, its age in maxtime */
nandgate	0:6dee052a3fa4	335	} else if (arp_table[i].ctime >= age_stable) {
nandgate	0:6dee052a3fa4	336	old_stable = i;
nandgate	0:6dee052a3fa4	337	age_stable = arp_table[i].ctime;
nandgate	0:6dee052a3fa4	338	}
nandgate	0:6dee052a3fa4	339	}
nandgate	0:6dee052a3fa4	340	}
nandgate	0:6dee052a3fa4	341	/* { we have no match } => try to create a new entry */
nandgate	0:6dee052a3fa4	342
nandgate	0:6dee052a3fa4	343	/* no empty entry found and not allowed to recycle? */
nandgate	0:6dee052a3fa4	344	if (((empty == ARP_TABLE_SIZE) && ((flags & ETHARP_TRY_HARD) == 0))
nandgate	0:6dee052a3fa4	345	/* or don't create new entry, only search? */
nandgate	0:6dee052a3fa4	346	\|\| ((flags & ETHARP_FIND_ONLY) != 0)) {
nandgate	0:6dee052a3fa4	347	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: no empty entry found and not allowed to recycle\n"));
nandgate	0:6dee052a3fa4	348	return (s8_t)ERR_MEM;
nandgate	0:6dee052a3fa4	349	}
nandgate	0:6dee052a3fa4	350
nandgate	0:6dee052a3fa4	351	/* b) choose the least destructive entry to recycle:
nandgate	0:6dee052a3fa4	352	* 1) empty entry
nandgate	0:6dee052a3fa4	353	* 2) oldest stable entry
nandgate	0:6dee052a3fa4	354	* 3) oldest pending entry without queued packets
nandgate	0:6dee052a3fa4	355	* 4) oldest pending entry with queued packets
nandgate	0:6dee052a3fa4	356	*
nandgate	0:6dee052a3fa4	357	* { ETHARP_TRY_HARD is set at this point }
nandgate	0:6dee052a3fa4	358	*/
nandgate	0:6dee052a3fa4	359
nandgate	0:6dee052a3fa4	360	/* 1) empty entry available? */
nandgate	0:6dee052a3fa4	361	if (empty < ARP_TABLE_SIZE) {
nandgate	0:6dee052a3fa4	362	i = empty;
nandgate	0:6dee052a3fa4	363	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting empty entry %"U16_F"\n", (u16_t)i));
nandgate	0:6dee052a3fa4	364	}
nandgate	0:6dee052a3fa4	365	/* 2) found recyclable stable entry? */
nandgate	0:6dee052a3fa4	366	else if (old_stable < ARP_TABLE_SIZE) {
nandgate	0:6dee052a3fa4	367	/* recycle oldest stable*/
nandgate	0:6dee052a3fa4	368	i = old_stable;
nandgate	0:6dee052a3fa4	369	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest stable entry %"U16_F"\n", (u16_t)i));
nandgate	0:6dee052a3fa4	370	#if ARP_QUEUEING
nandgate	0:6dee052a3fa4	371	/* no queued packets should exist on stable entries */
nandgate	0:6dee052a3fa4	372	LWIP_ASSERT("arp_table[i].q == NULL", arp_table[i].q == NULL);
nandgate	0:6dee052a3fa4	373	#endif
nandgate	0:6dee052a3fa4	374	/* 3) found recyclable pending entry without queued packets? */
nandgate	0:6dee052a3fa4	375	} else if (old_pending < ARP_TABLE_SIZE) {
nandgate	0:6dee052a3fa4	376	/* recycle oldest pending */
nandgate	0:6dee052a3fa4	377	i = old_pending;
nandgate	0:6dee052a3fa4	378	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest pending entry %"U16_F" (without queue)\n", (u16_t)i));
nandgate	0:6dee052a3fa4	379	#if ARP_QUEUEING
nandgate	0:6dee052a3fa4	380	/* 4) found recyclable pending entry with queued packets? */
nandgate	0:6dee052a3fa4	381	} else if (old_queue < ARP_TABLE_SIZE) {
nandgate	0:6dee052a3fa4	382	/* recycle oldest pending */
nandgate	0:6dee052a3fa4	383	i = old_queue;
nandgate	0:6dee052a3fa4	384	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)));
nandgate	0:6dee052a3fa4	385	free_etharp_q(arp_table[i].q);
nandgate	0:6dee052a3fa4	386	arp_table[i].q = NULL;
nandgate	0:6dee052a3fa4	387	#endif
nandgate	0:6dee052a3fa4	388	/* no empty or recyclable entries found */
nandgate	0:6dee052a3fa4	389	} else {
nandgate	0:6dee052a3fa4	390	return (s8_t)ERR_MEM;
nandgate	0:6dee052a3fa4	391	}
nandgate	0:6dee052a3fa4	392
nandgate	0:6dee052a3fa4	393	/* { empty or recyclable entry found } */
nandgate	0:6dee052a3fa4	394	LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
nandgate	0:6dee052a3fa4	395
nandgate	0:6dee052a3fa4	396	if (arp_table[i].state != ETHARP_STATE_EMPTY)
nandgate	0:6dee052a3fa4	397	{
nandgate	0:6dee052a3fa4	398	snmp_delete_arpidx_tree(arp_table[i].netif, &arp_table[i].ipaddr);
nandgate	0:6dee052a3fa4	399	}
nandgate	0:6dee052a3fa4	400	/* recycle entry (no-op for an already empty entry) */
nandgate	0:6dee052a3fa4	401	arp_table[i].state = ETHARP_STATE_EMPTY;
nandgate	0:6dee052a3fa4	402
nandgate	0:6dee052a3fa4	403	/* IP address given? */
nandgate	0:6dee052a3fa4	404	if (ipaddr != NULL) {
nandgate	0:6dee052a3fa4	405	/* set IP address */
nandgate	0:6dee052a3fa4	406	ip_addr_set(&arp_table[i].ipaddr, ipaddr);
nandgate	0:6dee052a3fa4	407	}
nandgate	0:6dee052a3fa4	408	arp_table[i].ctime = 0;
nandgate	0:6dee052a3fa4	409	#if LWIP_NETIF_HWADDRHINT
nandgate	0:6dee052a3fa4	410	NETIF_SET_HINT(netif, i);
nandgate	0:6dee052a3fa4	411	#else /* #if LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	412	etharp_cached_entry = i;
nandgate	0:6dee052a3fa4	413	#endif /* #if LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	414	return (err_t)i;
nandgate	0:6dee052a3fa4	415	}
nandgate	0:6dee052a3fa4	416
nandgate	0:6dee052a3fa4	417	/**
nandgate	0:6dee052a3fa4	418	* Send an IP packet on the network using netif->linkoutput
nandgate	0:6dee052a3fa4	419	* The ethernet header is filled in before sending.
nandgate	0:6dee052a3fa4	420	*
nandgate	0:6dee052a3fa4	421	* @params netif the lwIP network interface on which to send the packet
nandgate	0:6dee052a3fa4	422	* @params p the packet to send, p->payload pointing to the (uninitialized) ethernet header
nandgate	0:6dee052a3fa4	423	* @params src the source MAC address to be copied into the ethernet header
nandgate	0:6dee052a3fa4	424	* @params dst the destination MAC address to be copied into the ethernet header
nandgate	0:6dee052a3fa4	425	* @return ERR_OK if the packet was sent, any other err_t on failure
nandgate	0:6dee052a3fa4	426	*/
nandgate	0:6dee052a3fa4	427	static err_t
nandgate	0:6dee052a3fa4	428	etharp_send_ip(struct netif netif, struct pbuf p, struct eth_addr src, struct eth_addr dst)
nandgate	0:6dee052a3fa4	429	{
nandgate	0:6dee052a3fa4	430	struct eth_hdr ethhdr = (struct eth_hdr )p->payload;
nandgate	0:6dee052a3fa4	431	u8_t k;
nandgate	0:6dee052a3fa4	432
nandgate	0:6dee052a3fa4	433	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
nandgate	0:6dee052a3fa4	434	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
nandgate	0:6dee052a3fa4	435	k = ETHARP_HWADDR_LEN;
nandgate	0:6dee052a3fa4	436	while(k > 0) {
nandgate	0:6dee052a3fa4	437	k--;
nandgate	0:6dee052a3fa4	438	ethhdr->dest.addr[k] = dst->addr[k];
nandgate	0:6dee052a3fa4	439	ethhdr->src.addr[k] = src->addr[k];
nandgate	0:6dee052a3fa4	440	}
nandgate	0:6dee052a3fa4	441	ethhdr->type = htons(ETHTYPE_IP);
nandgate	0:6dee052a3fa4	442	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_send_ip: sending packet %p\n", (void *)p));
nandgate	0:6dee052a3fa4	443	/* send the packet */
nandgate	0:6dee052a3fa4	444	return netif->linkoutput(netif, p);
nandgate	0:6dee052a3fa4	445	}
nandgate	0:6dee052a3fa4	446
nandgate	0:6dee052a3fa4	447	/**
nandgate	0:6dee052a3fa4	448	* Update (or insert) a IP/MAC address pair in the ARP cache.
nandgate	0:6dee052a3fa4	449	*
nandgate	0:6dee052a3fa4	450	* If a pending entry is resolved, any queued packets will be sent
nandgate	0:6dee052a3fa4	451	* at this point.
nandgate	0:6dee052a3fa4	452	*
nandgate	0:6dee052a3fa4	453	* @param ipaddr IP address of the inserted ARP entry.
nandgate	0:6dee052a3fa4	454	* @param ethaddr Ethernet address of the inserted ARP entry.
nandgate	0:6dee052a3fa4	455	* @param flags Defines behaviour:
nandgate	0:6dee052a3fa4	456	* - ETHARP_TRY_HARD Allows ARP to insert this as a new item. If not specified,
nandgate	0:6dee052a3fa4	457	* only existing ARP entries will be updated.
nandgate	0:6dee052a3fa4	458	*
nandgate	0:6dee052a3fa4	459	* @return
nandgate	0:6dee052a3fa4	460	* - ERR_OK Succesfully updated ARP cache.
nandgate	0:6dee052a3fa4	461	* - ERR_MEM If we could not add a new ARP entry when ETHARP_TRY_HARD was set.
nandgate	0:6dee052a3fa4	462	* - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
nandgate	0:6dee052a3fa4	463	*
nandgate	0:6dee052a3fa4	464	* @see pbuf_free()
nandgate	0:6dee052a3fa4	465	*/
nandgate	0:6dee052a3fa4	466	static err_t
nandgate	0:6dee052a3fa4	467	update_arp_entry(struct netif netif, struct ip_addr ipaddr, struct eth_addr *ethaddr, u8_t flags)
nandgate	0:6dee052a3fa4	468	{
nandgate	0:6dee052a3fa4	469	s8_t i;
nandgate	0:6dee052a3fa4	470	u8_t k;
nandgate	0:6dee052a3fa4	471	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| 3, ("update_arp_entry()\n"));
nandgate	0:6dee052a3fa4	472	LWIP_ASSERT("netif->hwaddr_len == ETHARP_HWADDR_LEN", netif->hwaddr_len == ETHARP_HWADDR_LEN);
nandgate	0:6dee052a3fa4	473	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",
nandgate	0:6dee052a3fa4	474	ip4_addr1(ipaddr), ip4_addr2(ipaddr), ip4_addr3(ipaddr), ip4_addr4(ipaddr),
nandgate	0:6dee052a3fa4	475	ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
nandgate	0:6dee052a3fa4	476	ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
nandgate	0:6dee052a3fa4	477	/* non-unicast address? */
nandgate	0:6dee052a3fa4	478	if (ip_addr_isany(ipaddr) \|\|
nandgate	0:6dee052a3fa4	479	ip_addr_isbroadcast(ipaddr, netif) \|\|
nandgate	0:6dee052a3fa4	480	ip_addr_ismulticast(ipaddr)) {
nandgate	0:6dee052a3fa4	481	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: will not add non-unicast IP address to ARP cache\n"));
nandgate	0:6dee052a3fa4	482	return ERR_ARG;
nandgate	0:6dee052a3fa4	483	}
nandgate	0:6dee052a3fa4	484	/* find or create ARP entry */
nandgate	0:6dee052a3fa4	485	#if LWIP_NETIF_HWADDRHINT
nandgate	0:6dee052a3fa4	486	i = find_entry(ipaddr, flags, netif);
nandgate	0:6dee052a3fa4	487	#else /* LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	488	i = find_entry(ipaddr, flags);
nandgate	0:6dee052a3fa4	489	#endif /* LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	490	/* bail out if no entry could be found */
nandgate	0:6dee052a3fa4	491	if (i < 0)
nandgate	0:6dee052a3fa4	492	return (err_t)i;
nandgate	0:6dee052a3fa4	493
nandgate	0:6dee052a3fa4	494	/* mark it stable */
nandgate	0:6dee052a3fa4	495	arp_table[i].state = ETHARP_STATE_STABLE;
nandgate	0:6dee052a3fa4	496	/* record network interface */
nandgate	0:6dee052a3fa4	497	arp_table[i].netif = netif;
nandgate	0:6dee052a3fa4	498
nandgate	0:6dee052a3fa4	499	/* insert in SNMP ARP index tree */
nandgate	0:6dee052a3fa4	500	snmp_insert_arpidx_tree(netif, &arp_table[i].ipaddr);
nandgate	0:6dee052a3fa4	501
nandgate	0:6dee052a3fa4	502	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: updating stable entry %"S16_F"\n", (s16_t)i));
nandgate	0:6dee052a3fa4	503	/* update address */
nandgate	0:6dee052a3fa4	504	k = ETHARP_HWADDR_LEN;
nandgate	0:6dee052a3fa4	505	while (k > 0) {
nandgate	0:6dee052a3fa4	506	k--;
nandgate	0:6dee052a3fa4	507	arp_table[i].ethaddr.addr[k] = ethaddr->addr[k];
nandgate	0:6dee052a3fa4	508	}
nandgate	0:6dee052a3fa4	509	/* reset time stamp */
nandgate	0:6dee052a3fa4	510	arp_table[i].ctime = 0;
nandgate	0:6dee052a3fa4	511	#if ARP_QUEUEING
nandgate	0:6dee052a3fa4	512	/* this is where we will send out queued packets! */
nandgate	0:6dee052a3fa4	513	while (arp_table[i].q != NULL) {
nandgate	0:6dee052a3fa4	514	struct pbuf *p;
nandgate	0:6dee052a3fa4	515	/* remember remainder of queue */
nandgate	0:6dee052a3fa4	516	struct etharp_q_entry *q = arp_table[i].q;
nandgate	0:6dee052a3fa4	517	/* pop first item off the queue */
nandgate	0:6dee052a3fa4	518	arp_table[i].q = q->next;
nandgate	0:6dee052a3fa4	519	/* get the packet pointer */
nandgate	0:6dee052a3fa4	520	p = q->p;
nandgate	0:6dee052a3fa4	521	/* now queue entry can be freed */
nandgate	0:6dee052a3fa4	522	memp_free(MEMP_ARP_QUEUE, q);
nandgate	0:6dee052a3fa4	523	/* send the queued IP packet */
nandgate	0:6dee052a3fa4	524	etharp_send_ip(netif, p, (struct eth_addr*)(netif->hwaddr), ethaddr);
nandgate	0:6dee052a3fa4	525	/* free the queued IP packet */
nandgate	0:6dee052a3fa4	526	pbuf_free(p);
nandgate	0:6dee052a3fa4	527	}
nandgate	0:6dee052a3fa4	528	#endif
nandgate	0:6dee052a3fa4	529	return ERR_OK;
nandgate	0:6dee052a3fa4	530	}
nandgate	0:6dee052a3fa4	531
nandgate	0:6dee052a3fa4	532	/**
nandgate	0:6dee052a3fa4	533	* Finds (stable) ethernet/IP address pair from ARP table
nandgate	0:6dee052a3fa4	534	* using interface and IP address index.
nandgate	0:6dee052a3fa4	535	* @note the addresses in the ARP table are in network order!
nandgate	0:6dee052a3fa4	536	*
nandgate	0:6dee052a3fa4	537	* @param netif points to interface index
nandgate	0:6dee052a3fa4	538	* @param ipaddr points to the (network order) IP address index
nandgate	0:6dee052a3fa4	539	* @param eth_ret points to return pointer
nandgate	0:6dee052a3fa4	540	* @param ip_ret points to return pointer
nandgate	0:6dee052a3fa4	541	* @return table index if found, -1 otherwise
nandgate	0:6dee052a3fa4	542	*/
nandgate	0:6dee052a3fa4	543	s8_t
nandgate	0:6dee052a3fa4	544	etharp_find_addr(struct netif netif, struct ip_addr ipaddr,
nandgate	0:6dee052a3fa4	545	struct eth_addr eth_ret, struct ip_addr ip_ret)
nandgate	0:6dee052a3fa4	546	{
nandgate	0:6dee052a3fa4	547	s8_t i;
nandgate	0:6dee052a3fa4	548
nandgate	0:6dee052a3fa4	549	LWIP_UNUSED_ARG(netif);
nandgate	0:6dee052a3fa4	550
nandgate	0:6dee052a3fa4	551	#if LWIP_NETIF_HWADDRHINT
nandgate	0:6dee052a3fa4	552	i = find_entry(ipaddr, ETHARP_FIND_ONLY, NULL);
nandgate	0:6dee052a3fa4	553	#else /* LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	554	i = find_entry(ipaddr, ETHARP_FIND_ONLY);
nandgate	0:6dee052a3fa4	555	#endif /* LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	556	if((i >= 0) && arp_table[i].state == ETHARP_STATE_STABLE) {
nandgate	0:6dee052a3fa4	557	*eth_ret = &arp_table[i].ethaddr;
nandgate	0:6dee052a3fa4	558	*ip_ret = &arp_table[i].ipaddr;
nandgate	0:6dee052a3fa4	559	return i;
nandgate	0:6dee052a3fa4	560	}
nandgate	0:6dee052a3fa4	561	return -1;
nandgate	0:6dee052a3fa4	562	}
nandgate	0:6dee052a3fa4	563
nandgate	0:6dee052a3fa4	564	/**
nandgate	0:6dee052a3fa4	565	* Updates the ARP table using the given IP packet.
nandgate	0:6dee052a3fa4	566	*
nandgate	0:6dee052a3fa4	567	* Uses the incoming IP packet's source address to update the
nandgate	0:6dee052a3fa4	568	* ARP cache for the local network. The function does not alter
nandgate	0:6dee052a3fa4	569	* or free the packet. This function must be called before the
nandgate	0:6dee052a3fa4	570	* packet p is passed to the IP layer.
nandgate	0:6dee052a3fa4	571	*
nandgate	0:6dee052a3fa4	572	* @param netif The lwIP network interface on which the IP packet pbuf arrived.
nandgate	0:6dee052a3fa4	573	* @param p The IP packet that arrived on netif.
nandgate	0:6dee052a3fa4	574	*
nandgate	0:6dee052a3fa4	575	* @return NULL
nandgate	0:6dee052a3fa4	576	*
nandgate	0:6dee052a3fa4	577	* @see pbuf_free()
nandgate	0:6dee052a3fa4	578	*/
nandgate	0:6dee052a3fa4	579	void
nandgate	0:6dee052a3fa4	580	etharp_ip_input(struct netif netif, struct pbuf p)
nandgate	0:6dee052a3fa4	581	{
nandgate	0:6dee052a3fa4	582	struct eth_hdr *ethhdr;
nandgate	0:6dee052a3fa4	583	struct ip_hdr *iphdr;
nandgate	0:6dee052a3fa4	584	LWIP_ERROR("netif != NULL", (netif != NULL), return;);
nandgate	0:6dee052a3fa4	585	/* Only insert an entry if the source IP address of the
nandgate	0:6dee052a3fa4	586	incoming IP packet comes from a host on the local network. */
nandgate	0:6dee052a3fa4	587	ethhdr = (struct eth_hdr *)p->payload;
nandgate	0:6dee052a3fa4	588	iphdr = (struct ip_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
nandgate	0:6dee052a3fa4	589	#if ETHARP_SUPPORT_VLAN
nandgate	0:6dee052a3fa4	590	if (ethhdr->type == ETHTYPE_VLAN) {
nandgate	0:6dee052a3fa4	591	iphdr = (struct ip_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
nandgate	0:6dee052a3fa4	592	}
nandgate	0:6dee052a3fa4	593	#endif /* ETHARP_SUPPORT_VLAN */
nandgate	0:6dee052a3fa4	594
nandgate	0:6dee052a3fa4	595	/* source is not on the local network? */
nandgate	0:6dee052a3fa4	596	if (!ip_addr_netcmp(&(iphdr->src), &(netif->ip_addr), &(netif->netmask))) {
nandgate	0:6dee052a3fa4	597	/* do nothing */
nandgate	0:6dee052a3fa4	598	return;
nandgate	0:6dee052a3fa4	599	}
nandgate	0:6dee052a3fa4	600
nandgate	0:6dee052a3fa4	601	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_ip_input: updating ETHARP table.\n"));
nandgate	0:6dee052a3fa4	602	/* update ARP table */
nandgate	0:6dee052a3fa4	603	/* @todo We could use ETHARP_TRY_HARD if we think we are going to talk
nandgate	0:6dee052a3fa4	604	* back soon (for example, if the destination IP address is ours. */
nandgate	0:6dee052a3fa4	605	update_arp_entry(netif, &(iphdr->src), &(ethhdr->src), 0);
nandgate	0:6dee052a3fa4	606	}
nandgate	0:6dee052a3fa4	607
nandgate	0:6dee052a3fa4	608
nandgate	0:6dee052a3fa4	609	/**
nandgate	0:6dee052a3fa4	610	* Responds to ARP requests to us. Upon ARP replies to us, add entry to cache
nandgate	0:6dee052a3fa4	611	* send out queued IP packets. Updates cache with snooped address pairs.
nandgate	0:6dee052a3fa4	612	*
nandgate	0:6dee052a3fa4	613	* Should be called for incoming ARP packets. The pbuf in the argument
nandgate	0:6dee052a3fa4	614	* is freed by this function.
nandgate	0:6dee052a3fa4	615	*
nandgate	0:6dee052a3fa4	616	* @param netif The lwIP network interface on which the ARP packet pbuf arrived.
nandgate	0:6dee052a3fa4	617	* @param ethaddr Ethernet address of netif.
nandgate	0:6dee052a3fa4	618	* @param p The ARP packet that arrived on netif. Is freed by this function.
nandgate	0:6dee052a3fa4	619	*
nandgate	0:6dee052a3fa4	620	* @return NULL
nandgate	0:6dee052a3fa4	621	*
nandgate	0:6dee052a3fa4	622	* @see pbuf_free()
nandgate	0:6dee052a3fa4	623	*/
nandgate	0:6dee052a3fa4	624	void
nandgate	0:6dee052a3fa4	625	etharp_arp_input(struct netif netif, struct eth_addr ethaddr, struct pbuf *p)
nandgate	0:6dee052a3fa4	626	{
nandgate	0:6dee052a3fa4	627	struct etharp_hdr *hdr;
nandgate	0:6dee052a3fa4	628	struct eth_hdr *ethhdr;
nandgate	0:6dee052a3fa4	629	/* these are aligned properly, whereas the ARP header fields might not be */
nandgate	0:6dee052a3fa4	630	struct ip_addr sipaddr, dipaddr;
nandgate	0:6dee052a3fa4	631	u8_t i;
nandgate	0:6dee052a3fa4	632	u8_t for_us;
nandgate	0:6dee052a3fa4	633	#if LWIP_AUTOIP
nandgate	0:6dee052a3fa4	634	const u8_t * ethdst_hwaddr;
nandgate	0:6dee052a3fa4	635	#endif /* LWIP_AUTOIP */
nandgate	0:6dee052a3fa4	636
nandgate	0:6dee052a3fa4	637	LWIP_ERROR("netif != NULL", (netif != NULL), return;);
nandgate	0:6dee052a3fa4	638
nandgate	0:6dee052a3fa4	639	/* drop short ARP packets: we have to check for p->len instead of p->tot_len here
nandgate	0:6dee052a3fa4	640	since a struct etharp_hdr is pointed to p->payload, so it musn't be chained! */
nandgate	0:6dee052a3fa4	641	if (p->len < SIZEOF_ETHARP_PACKET) {
nandgate	0:6dee052a3fa4	642	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| 1, ("etharp_arp_input: packet dropped, too short (%"S16_F"/%"S16_F")\n", p->tot_len, (s16_t)SIZEOF_ETHARP_PACKET));
nandgate	0:6dee052a3fa4	643	ETHARP_STATS_INC(etharp.lenerr);
nandgate	0:6dee052a3fa4	644	ETHARP_STATS_INC(etharp.drop);
nandgate	0:6dee052a3fa4	645	pbuf_free(p);
nandgate	0:6dee052a3fa4	646	return;
nandgate	0:6dee052a3fa4	647	}
nandgate	0:6dee052a3fa4	648
nandgate	0:6dee052a3fa4	649	ethhdr = (struct eth_hdr *)p->payload;
nandgate	0:6dee052a3fa4	650	hdr = (struct etharp_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
nandgate	0:6dee052a3fa4	651	#if ETHARP_SUPPORT_VLAN
nandgate	0:6dee052a3fa4	652	if (ethhdr->type == ETHTYPE_VLAN) {
nandgate	0:6dee052a3fa4	653	hdr = (struct etharp_hdr )(((u8_t)ethhdr) + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
nandgate	0:6dee052a3fa4	654	}
nandgate	0:6dee052a3fa4	655	#endif /* ETHARP_SUPPORT_VLAN */
nandgate	0:6dee052a3fa4	656
nandgate	0:6dee052a3fa4	657	/* RFC 826 "Packet Reception": */
nandgate	0:6dee052a3fa4	658	if ((hdr->hwtype != htons(HWTYPE_ETHERNET)) \|\|
nandgate	0:6dee052a3fa4	659	(hdr->_hwlen_protolen != htons((ETHARP_HWADDR_LEN << 8) \| sizeof(struct ip_addr))) \|\|
nandgate	0:6dee052a3fa4	660	(hdr->proto != htons(ETHTYPE_IP)) \|\|
nandgate	0:6dee052a3fa4	661	(ethhdr->type != htons(ETHTYPE_ARP))) {
nandgate	0:6dee052a3fa4	662	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| 1,
nandgate	0:6dee052a3fa4	663	("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",
nandgate	0:6dee052a3fa4	664	hdr->hwtype, ARPH_HWLEN(hdr), hdr->proto, ARPH_PROTOLEN(hdr), ethhdr->type));
nandgate	0:6dee052a3fa4	665	ETHARP_STATS_INC(etharp.proterr);
nandgate	0:6dee052a3fa4	666	ETHARP_STATS_INC(etharp.drop);
nandgate	0:6dee052a3fa4	667	pbuf_free(p);
nandgate	0:6dee052a3fa4	668	return;
nandgate	0:6dee052a3fa4	669	}
nandgate	0:6dee052a3fa4	670	ETHARP_STATS_INC(etharp.recv);
nandgate	0:6dee052a3fa4	671
nandgate	0:6dee052a3fa4	672	#if LWIP_AUTOIP
nandgate	0:6dee052a3fa4	673	/* We have to check if a host already has configured our random
nandgate	0:6dee052a3fa4	674	* created link local address and continously check if there is
nandgate	0:6dee052a3fa4	675	* a host with this IP-address so we can detect collisions */
nandgate	0:6dee052a3fa4	676	autoip_arp_reply(netif, hdr);
nandgate	0:6dee052a3fa4	677	#endif /* LWIP_AUTOIP */
nandgate	0:6dee052a3fa4	678
nandgate	0:6dee052a3fa4	679	/* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
nandgate	0:6dee052a3fa4	680	* structure packing (not using structure copy which breaks strict-aliasing rules). */
nandgate	0:6dee052a3fa4	681	SMEMCPY(&sipaddr, &hdr->sipaddr, sizeof(sipaddr));
nandgate	0:6dee052a3fa4	682	SMEMCPY(&dipaddr, &hdr->dipaddr, sizeof(dipaddr));
nandgate	0:6dee052a3fa4	683
nandgate	0:6dee052a3fa4	684	/* this interface is not configured? */
nandgate	0:6dee052a3fa4	685	if (netif->ip_addr.addr == 0) {
nandgate	0:6dee052a3fa4	686	for_us = 0;
nandgate	0:6dee052a3fa4	687	} else {
nandgate	0:6dee052a3fa4	688	/* ARP packet directed to us? */
nandgate	0:6dee052a3fa4	689	for_us = ip_addr_cmp(&dipaddr, &(netif->ip_addr));
nandgate	0:6dee052a3fa4	690	}
nandgate	0:6dee052a3fa4	691
nandgate	0:6dee052a3fa4	692	/* ARP message directed to us? */
nandgate	0:6dee052a3fa4	693	if (for_us) {
nandgate	0:6dee052a3fa4	694	/* add IP address in ARP cache; assume requester wants to talk to us.
nandgate	0:6dee052a3fa4	695	* can result in directly sending the queued packets for this host. */
nandgate	0:6dee052a3fa4	696	update_arp_entry(netif, &sipaddr, &(hdr->shwaddr), ETHARP_TRY_HARD);
nandgate	0:6dee052a3fa4	697	/* ARP message not directed to us? */
nandgate	0:6dee052a3fa4	698	} else {
nandgate	0:6dee052a3fa4	699	/* update the source IP address in the cache, if present */
nandgate	0:6dee052a3fa4	700	update_arp_entry(netif, &sipaddr, &(hdr->shwaddr), 0);
nandgate	0:6dee052a3fa4	701	}
nandgate	0:6dee052a3fa4	702
nandgate	0:6dee052a3fa4	703	/* now act on the message itself */
nandgate	0:6dee052a3fa4	704	switch (htons(hdr->opcode)) {
nandgate	0:6dee052a3fa4	705	/* ARP request? */
nandgate	0:6dee052a3fa4	706	case ARP_REQUEST:
nandgate	0:6dee052a3fa4	707	/* ARP request. If it asked for our address, we send out a
nandgate	0:6dee052a3fa4	708	* reply. In any case, we time-stamp any existing ARP entry,
nandgate	0:6dee052a3fa4	709	* and possiby send out an IP packet that was queued on it. */
nandgate	0:6dee052a3fa4	710
nandgate	0:6dee052a3fa4	711	LWIP_DEBUGF (ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP request\n"));
nandgate	0:6dee052a3fa4	712	/* ARP request for our address? */
nandgate	0:6dee052a3fa4	713	if (for_us) {
nandgate	0:6dee052a3fa4	714
nandgate	0:6dee052a3fa4	715	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: replying to ARP request for our IP address\n"));
nandgate	0:6dee052a3fa4	716	/* Re-use pbuf to send ARP reply.
nandgate	0:6dee052a3fa4	717	Since we are re-using an existing pbuf, we can't call etharp_raw since
nandgate	0:6dee052a3fa4	718	that would allocate a new pbuf. */
nandgate	0:6dee052a3fa4	719	hdr->opcode = htons(ARP_REPLY);
nandgate	0:6dee052a3fa4	720
nandgate	0:6dee052a3fa4	721	hdr->dipaddr = hdr->sipaddr;
nandgate	0:6dee052a3fa4	722	SMEMCPY(&hdr->sipaddr, &netif->ip_addr, sizeof(hdr->sipaddr));
nandgate	0:6dee052a3fa4	723
nandgate	0:6dee052a3fa4	724	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
nandgate	0:6dee052a3fa4	725	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
nandgate	0:6dee052a3fa4	726	i = ETHARP_HWADDR_LEN;
nandgate	0:6dee052a3fa4	727	#if LWIP_AUTOIP
nandgate	0:6dee052a3fa4	728	/* If we are using Link-Local, ARP packets must be broadcast on the
nandgate	0:6dee052a3fa4	729	* link layer. (See RFC3927 Section 2.5) */
nandgate	0:6dee052a3fa4	730	ethdst_hwaddr = ((netif->autoip != NULL) && (netif->autoip->state != AUTOIP_STATE_OFF)) ? (u8_t*)(ethbroadcast.addr) : hdr->shwaddr.addr;
nandgate	0:6dee052a3fa4	731	#endif /* LWIP_AUTOIP */
nandgate	0:6dee052a3fa4	732
nandgate	0:6dee052a3fa4	733	while(i > 0) {
nandgate	0:6dee052a3fa4	734	i--;
nandgate	0:6dee052a3fa4	735	hdr->dhwaddr.addr[i] = hdr->shwaddr.addr[i];
nandgate	0:6dee052a3fa4	736	#if LWIP_AUTOIP
nandgate	0:6dee052a3fa4	737	ethhdr->dest.addr[i] = ethdst_hwaddr[i];
nandgate	0:6dee052a3fa4	738	#else /* LWIP_AUTOIP */
nandgate	0:6dee052a3fa4	739	ethhdr->dest.addr[i] = hdr->shwaddr.addr[i];
nandgate	0:6dee052a3fa4	740	#endif /* LWIP_AUTOIP */
nandgate	0:6dee052a3fa4	741	hdr->shwaddr.addr[i] = ethaddr->addr[i];
nandgate	0:6dee052a3fa4	742	ethhdr->src.addr[i] = ethaddr->addr[i];
nandgate	0:6dee052a3fa4	743	}
nandgate	0:6dee052a3fa4	744
nandgate	0:6dee052a3fa4	745	/* hwtype, hwaddr_len, proto, protolen and the type in the ethernet header
nandgate	0:6dee052a3fa4	746	are already correct, we tested that before */
nandgate	0:6dee052a3fa4	747
nandgate	0:6dee052a3fa4	748	/* return ARP reply */
nandgate	0:6dee052a3fa4	749	netif->linkoutput(netif, p);
nandgate	0:6dee052a3fa4	750	/* we are not configured? */
nandgate	0:6dee052a3fa4	751	} else if (netif->ip_addr.addr == 0) {
nandgate	0:6dee052a3fa4	752	/* { for_us == 0 and netif->ip_addr.addr == 0 } */
nandgate	0:6dee052a3fa4	753	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: we are unconfigured, ARP request ignored.\n"));
nandgate	0:6dee052a3fa4	754	/* request was not directed to us */
nandgate	0:6dee052a3fa4	755	} else {
nandgate	0:6dee052a3fa4	756	/* { for_us == 0 and netif->ip_addr.addr != 0 } */
nandgate	0:6dee052a3fa4	757	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: ARP request was not for us.\n"));
nandgate	0:6dee052a3fa4	758	}
nandgate	0:6dee052a3fa4	759	break;
nandgate	0:6dee052a3fa4	760	case ARP_REPLY:
nandgate	0:6dee052a3fa4	761	/* ARP reply. We already updated the ARP cache earlier. */
nandgate	0:6dee052a3fa4	762	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP reply\n"));
nandgate	0:6dee052a3fa4	763	#if (LWIP_DHCP && DHCP_DOES_ARP_CHECK)
nandgate	0:6dee052a3fa4	764	/* DHCP wants to know about ARP replies from any host with an
nandgate	0:6dee052a3fa4	765	* IP address also offered to us by the DHCP server. We do not
nandgate	0:6dee052a3fa4	766	* want to take a duplicate IP address on a single network.
nandgate	0:6dee052a3fa4	767	* @todo How should we handle redundant (fail-over) interfaces? */
nandgate	0:6dee052a3fa4	768	dhcp_arp_reply(netif, &sipaddr);
nandgate	0:6dee052a3fa4	769	#endif
nandgate	0:6dee052a3fa4	770	break;
nandgate	0:6dee052a3fa4	771	default:
nandgate	0:6dee052a3fa4	772	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: ARP unknown opcode type %"S16_F"\n", htons(hdr->opcode)));
nandgate	0:6dee052a3fa4	773	ETHARP_STATS_INC(etharp.err);
nandgate	0:6dee052a3fa4	774	break;
nandgate	0:6dee052a3fa4	775	}
nandgate	0:6dee052a3fa4	776	/* free ARP packet */
nandgate	0:6dee052a3fa4	777	pbuf_free(p);
nandgate	0:6dee052a3fa4	778	}
nandgate	0:6dee052a3fa4	779
nandgate	0:6dee052a3fa4	780	/**
nandgate	0:6dee052a3fa4	781	* Resolve and fill-in Ethernet address header for outgoing IP packet.
nandgate	0:6dee052a3fa4	782	*
nandgate	0:6dee052a3fa4	783	* For IP multicast and broadcast, corresponding Ethernet addresses
nandgate	0:6dee052a3fa4	784	* are selected and the packet is transmitted on the link.
nandgate	0:6dee052a3fa4	785	*
nandgate	0:6dee052a3fa4	786	* For unicast addresses, the packet is submitted to etharp_query(). In
nandgate	0:6dee052a3fa4	787	* case the IP address is outside the local network, the IP address of
nandgate	0:6dee052a3fa4	788	* the gateway is used.
nandgate	0:6dee052a3fa4	789	*
nandgate	0:6dee052a3fa4	790	* @param netif The lwIP network interface which the IP packet will be sent on.
nandgate	0:6dee052a3fa4	791	* @param q The pbuf(s) containing the IP packet to be sent.
nandgate	0:6dee052a3fa4	792	* @param ipaddr The IP address of the packet destination.
nandgate	0:6dee052a3fa4	793	*
nandgate	0:6dee052a3fa4	794	* @return
nandgate	0:6dee052a3fa4	795	* - ERR_RTE No route to destination (no gateway to external networks),
nandgate	0:6dee052a3fa4	796	* or the return type of either etharp_query() or etharp_send_ip().
nandgate	0:6dee052a3fa4	797	*/
nandgate	0:6dee052a3fa4	798	err_t
nandgate	0:6dee052a3fa4	799	etharp_output(struct netif netif, struct pbuf q, struct ip_addr *ipaddr)
nandgate	0:6dee052a3fa4	800	{
nandgate	0:6dee052a3fa4	801	struct eth_addr *dest, mcastaddr;
nandgate	0:6dee052a3fa4	802
nandgate	0:6dee052a3fa4	803	/* make room for Ethernet header - should not fail */
nandgate	0:6dee052a3fa4	804	if (pbuf_header(q, sizeof(struct eth_hdr)) != 0) {
nandgate	0:6dee052a3fa4	805	/* bail out */
nandgate	0:6dee052a3fa4	806	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| 2, ("etharp_output: could not allocate room for header.\n"));
nandgate	0:6dee052a3fa4	807	LINK_STATS_INC(link.lenerr);
nandgate	0:6dee052a3fa4	808	return ERR_BUF;
nandgate	0:6dee052a3fa4	809	}
nandgate	0:6dee052a3fa4	810
nandgate	0:6dee052a3fa4	811	/* assume unresolved Ethernet address */
nandgate	0:6dee052a3fa4	812	dest = NULL;
nandgate	0:6dee052a3fa4	813	/* Determine on destination hardware address. Broadcasts and multicasts
nandgate	0:6dee052a3fa4	814	* are special, other IP addresses are looked up in the ARP table. */
nandgate	0:6dee052a3fa4	815
nandgate	0:6dee052a3fa4	816	/* broadcast destination IP address? */
nandgate	0:6dee052a3fa4	817	if (ip_addr_isbroadcast(ipaddr, netif)) {
nandgate	0:6dee052a3fa4	818	/* broadcast on Ethernet also */
nandgate	0:6dee052a3fa4	819	dest = (struct eth_addr *)&ethbroadcast;
nandgate	0:6dee052a3fa4	820	/* multicast destination IP address? */
nandgate	0:6dee052a3fa4	821	} else if (ip_addr_ismulticast(ipaddr)) {
nandgate	0:6dee052a3fa4	822	/* Hash IP multicast address to MAC address.*/
nandgate	0:6dee052a3fa4	823	mcastaddr.addr[0] = 0x01;
nandgate	0:6dee052a3fa4	824	mcastaddr.addr[1] = 0x00;
nandgate	0:6dee052a3fa4	825	mcastaddr.addr[2] = 0x5e;
nandgate	0:6dee052a3fa4	826	mcastaddr.addr[3] = ip4_addr2(ipaddr) & 0x7f;
nandgate	0:6dee052a3fa4	827	mcastaddr.addr[4] = ip4_addr3(ipaddr);
nandgate	0:6dee052a3fa4	828	mcastaddr.addr[5] = ip4_addr4(ipaddr);
nandgate	0:6dee052a3fa4	829	/* destination Ethernet address is multicast */
nandgate	0:6dee052a3fa4	830	dest = &mcastaddr;
nandgate	0:6dee052a3fa4	831	/* unicast destination IP address? */
nandgate	0:6dee052a3fa4	832	} else {
nandgate	0:6dee052a3fa4	833	/* outside local network? */
nandgate	0:6dee052a3fa4	834	if (!ip_addr_netcmp(ipaddr, &(netif->ip_addr), &(netif->netmask))) {
nandgate	0:6dee052a3fa4	835	/* interface has default gateway? */
nandgate	0:6dee052a3fa4	836	if (netif->gw.addr != 0) {
nandgate	0:6dee052a3fa4	837	/* send to hardware address of default gateway IP address */
nandgate	0:6dee052a3fa4	838	ipaddr = &(netif->gw);
nandgate	0:6dee052a3fa4	839	/* no default gateway available */
nandgate	0:6dee052a3fa4	840	} else {
nandgate	0:6dee052a3fa4	841	/* no route to destination error (default gateway missing) */
nandgate	0:6dee052a3fa4	842	return ERR_RTE;
nandgate	0:6dee052a3fa4	843	}
nandgate	0:6dee052a3fa4	844	}
nandgate	0:6dee052a3fa4	845	/* queue on destination Ethernet address belonging to ipaddr */
nandgate	0:6dee052a3fa4	846	return etharp_query(netif, ipaddr, q);
nandgate	0:6dee052a3fa4	847	}
nandgate	0:6dee052a3fa4	848
nandgate	0:6dee052a3fa4	849	/* continuation for multicast/broadcast destinations */
nandgate	0:6dee052a3fa4	850	/* obtain source Ethernet address of the given interface */
nandgate	0:6dee052a3fa4	851	/* send packet directly on the link */
nandgate	0:6dee052a3fa4	852	return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr), dest);
nandgate	0:6dee052a3fa4	853	}
nandgate	0:6dee052a3fa4	854
nandgate	0:6dee052a3fa4	855	/**
nandgate	0:6dee052a3fa4	856	* Send an ARP request for the given IP address and/or queue a packet.
nandgate	0:6dee052a3fa4	857	*
nandgate	0:6dee052a3fa4	858	* If the IP address was not yet in the cache, a pending ARP cache entry
nandgate	0:6dee052a3fa4	859	* is added and an ARP request is sent for the given address. The packet
nandgate	0:6dee052a3fa4	860	* is queued on this entry.
nandgate	0:6dee052a3fa4	861	*
nandgate	0:6dee052a3fa4	862	* If the IP address was already pending in the cache, a new ARP request
nandgate	0:6dee052a3fa4	863	* is sent for the given address. The packet is queued on this entry.
nandgate	0:6dee052a3fa4	864	*
nandgate	0:6dee052a3fa4	865	* If the IP address was already stable in the cache, and a packet is
nandgate	0:6dee052a3fa4	866	* given, it is directly sent and no ARP request is sent out.
nandgate	0:6dee052a3fa4	867	*
nandgate	0:6dee052a3fa4	868	* If the IP address was already stable in the cache, and no packet is
nandgate	0:6dee052a3fa4	869	* given, an ARP request is sent out.
nandgate	0:6dee052a3fa4	870	*
nandgate	0:6dee052a3fa4	871	* @param netif The lwIP network interface on which ipaddr
nandgate	0:6dee052a3fa4	872	* must be queried for.
nandgate	0:6dee052a3fa4	873	* @param ipaddr The IP address to be resolved.
nandgate	0:6dee052a3fa4	874	* @param q If non-NULL, a pbuf that must be delivered to the IP address.
nandgate	0:6dee052a3fa4	875	* q is not freed by this function.
nandgate	0:6dee052a3fa4	876	*
nandgate	0:6dee052a3fa4	877	* @note q must only be ONE packet, not a packet queue!
nandgate	0:6dee052a3fa4	878	*
nandgate	0:6dee052a3fa4	879	* @return
nandgate	0:6dee052a3fa4	880	* - ERR_BUF Could not make room for Ethernet header.
nandgate	0:6dee052a3fa4	881	* - ERR_MEM Hardware address unknown, and no more ARP entries available
nandgate	0:6dee052a3fa4	882	* to query for address or queue the packet.
nandgate	0:6dee052a3fa4	883	* - ERR_MEM Could not queue packet due to memory shortage.
nandgate	0:6dee052a3fa4	884	* - ERR_RTE No route to destination (no gateway to external networks).
nandgate	0:6dee052a3fa4	885	* - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
nandgate	0:6dee052a3fa4	886	*
nandgate	0:6dee052a3fa4	887	*/
nandgate	0:6dee052a3fa4	888	err_t
nandgate	0:6dee052a3fa4	889	etharp_query(struct netif netif, struct ip_addr ipaddr, struct pbuf *q)
nandgate	0:6dee052a3fa4	890	{
nandgate	0:6dee052a3fa4	891	struct eth_addr * srcaddr = (struct eth_addr *)netif->hwaddr;
nandgate	0:6dee052a3fa4	892	err_t result = ERR_MEM;
nandgate	0:6dee052a3fa4	893	s8_t i; /* ARP entry index */
nandgate	0:6dee052a3fa4	894
nandgate	0:6dee052a3fa4	895	/* non-unicast address? */
nandgate	0:6dee052a3fa4	896	if (ip_addr_isbroadcast(ipaddr, netif) \|\|
nandgate	0:6dee052a3fa4	897	ip_addr_ismulticast(ipaddr) \|\|
nandgate	0:6dee052a3fa4	898	ip_addr_isany(ipaddr)) {
nandgate	0:6dee052a3fa4	899	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: will not add non-unicast IP address to ARP cache\n"));
nandgate	0:6dee052a3fa4	900	return ERR_ARG;
nandgate	0:6dee052a3fa4	901	}
nandgate	0:6dee052a3fa4	902
nandgate	0:6dee052a3fa4	903	/* find entry in ARP cache, ask to create entry if queueing packet */
nandgate	0:6dee052a3fa4	904	#if LWIP_NETIF_HWADDRHINT
nandgate	0:6dee052a3fa4	905	i = find_entry(ipaddr, ETHARP_TRY_HARD, netif);
nandgate	0:6dee052a3fa4	906	#else /* LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	907	i = find_entry(ipaddr, ETHARP_TRY_HARD);
nandgate	0:6dee052a3fa4	908	#endif /* LWIP_NETIF_HWADDRHINT */
nandgate	0:6dee052a3fa4	909
nandgate	0:6dee052a3fa4	910	/* could not find or create entry? */
nandgate	0:6dee052a3fa4	911	if (i < 0) {
nandgate	0:6dee052a3fa4	912	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: could not create ARP entry\n"));
nandgate	0:6dee052a3fa4	913	if (q) {
nandgate	0:6dee052a3fa4	914	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: packet dropped\n"));
nandgate	0:6dee052a3fa4	915	ETHARP_STATS_INC(etharp.memerr);
nandgate	0:6dee052a3fa4	916	}
nandgate	0:6dee052a3fa4	917	return (err_t)i;
nandgate	0:6dee052a3fa4	918	}
nandgate	0:6dee052a3fa4	919
nandgate	0:6dee052a3fa4	920	/* mark a fresh entry as pending (we just sent a request) */
nandgate	0:6dee052a3fa4	921	if (arp_table[i].state == ETHARP_STATE_EMPTY) {
nandgate	0:6dee052a3fa4	922	arp_table[i].state = ETHARP_STATE_PENDING;
nandgate	0:6dee052a3fa4	923	}
nandgate	0:6dee052a3fa4	924
nandgate	0:6dee052a3fa4	925	/* { i is either a STABLE or (new or existing) PENDING entry } */
nandgate	0:6dee052a3fa4	926	LWIP_ASSERT("arp_table[i].state == PENDING or STABLE",
nandgate	0:6dee052a3fa4	927	((arp_table[i].state == ETHARP_STATE_PENDING) \|\|
nandgate	0:6dee052a3fa4	928	(arp_table[i].state == ETHARP_STATE_STABLE)));
nandgate	0:6dee052a3fa4	929
nandgate	0:6dee052a3fa4	930	/* do we have a pending entry? or an implicit query request? */
nandgate	0:6dee052a3fa4	931	if ((arp_table[i].state == ETHARP_STATE_PENDING) \|\| (q == NULL)) {
nandgate	0:6dee052a3fa4	932	/* try to resolve it; send out ARP request */
nandgate	0:6dee052a3fa4	933	result = etharp_request(netif, ipaddr);
nandgate	0:6dee052a3fa4	934	if (result != ERR_OK) {
nandgate	0:6dee052a3fa4	935	/* ARP request couldn't be sent */
nandgate	0:6dee052a3fa4	936	/* We don't re-send arp request in etharp_tmr, but we still queue packets,
nandgate	0:6dee052a3fa4	937	since this failure could be temporary, and the next packet calling
nandgate	0:6dee052a3fa4	938	etharp_query again could lead to sending the queued packets. */
nandgate	0:6dee052a3fa4	939	}
nandgate	0:6dee052a3fa4	940	}
nandgate	0:6dee052a3fa4	941
nandgate	0:6dee052a3fa4	942	/* packet given? */
nandgate	0:6dee052a3fa4	943	if (q != NULL) {
nandgate	0:6dee052a3fa4	944	/* stable entry? */
nandgate	0:6dee052a3fa4	945	if (arp_table[i].state == ETHARP_STATE_STABLE) {
nandgate	0:6dee052a3fa4	946	/* we have a valid IP->Ethernet address mapping */
nandgate	0:6dee052a3fa4	947	/* send the packet */
nandgate	0:6dee052a3fa4	948	result = etharp_send_ip(netif, q, srcaddr, &(arp_table[i].ethaddr));
nandgate	0:6dee052a3fa4	949	/* pending entry? (either just created or already pending */
nandgate	0:6dee052a3fa4	950	} else if (arp_table[i].state == ETHARP_STATE_PENDING) {
nandgate	0:6dee052a3fa4	951	#if ARP_QUEUEING /* queue the given q packet */
nandgate	0:6dee052a3fa4	952	struct pbuf *p;
nandgate	0:6dee052a3fa4	953	int copy_needed = 0;
nandgate	0:6dee052a3fa4	954	/* IF q includes a PBUF_REF, PBUF_POOL or PBUF_RAM, we have no choice but
nandgate	0:6dee052a3fa4	955	* to copy the whole queue into a new PBUF_RAM (see bug #11400)
nandgate	0:6dee052a3fa4	956	* PBUF_ROMs can be left as they are, since ROM must not get changed. */
nandgate	0:6dee052a3fa4	957	p = q;
nandgate	0:6dee052a3fa4	958	while (p) {
nandgate	0:6dee052a3fa4	959	LWIP_ASSERT("no packet queues allowed!", (p->len != p->tot_len) \|\| (p->next == 0));
nandgate	0:6dee052a3fa4	960	if(p->type != PBUF_ROM) {
nandgate	0:6dee052a3fa4	961	copy_needed = 1;
nandgate	0:6dee052a3fa4	962	break;
nandgate	0:6dee052a3fa4	963	}
nandgate	0:6dee052a3fa4	964	p = p->next;
nandgate	0:6dee052a3fa4	965	}
nandgate	0:6dee052a3fa4	966	if(copy_needed) {
nandgate	0:6dee052a3fa4	967	/* copy the whole packet into new pbufs */
nandgate	0:6dee052a3fa4	968	p = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
nandgate	0:6dee052a3fa4	969	if(p != NULL) {
nandgate	0:6dee052a3fa4	970	if (pbuf_copy(p, q) != ERR_OK) {
nandgate	0:6dee052a3fa4	971	pbuf_free(p);
nandgate	0:6dee052a3fa4	972	p = NULL;
nandgate	0:6dee052a3fa4	973	}
nandgate	0:6dee052a3fa4	974	}
nandgate	0:6dee052a3fa4	975	} else {
nandgate	0:6dee052a3fa4	976	/* referencing the old pbuf is enough */
nandgate	0:6dee052a3fa4	977	p = q;
nandgate	0:6dee052a3fa4	978	pbuf_ref(p);
nandgate	0:6dee052a3fa4	979	}
nandgate	0:6dee052a3fa4	980	/* packet could be taken over? */
nandgate	0:6dee052a3fa4	981	if (p != NULL) {
nandgate	0:6dee052a3fa4	982	/* queue packet ... */
nandgate	0:6dee052a3fa4	983	struct etharp_q_entry *new_entry;
nandgate	0:6dee052a3fa4	984	/* allocate a new arp queue entry */
nandgate	0:6dee052a3fa4	985	new_entry = memp_malloc(MEMP_ARP_QUEUE);
nandgate	0:6dee052a3fa4	986	if (new_entry != NULL) {
nandgate	0:6dee052a3fa4	987	new_entry->next = 0;
nandgate	0:6dee052a3fa4	988	new_entry->p = p;
nandgate	0:6dee052a3fa4	989	if(arp_table[i].q != NULL) {
nandgate	0:6dee052a3fa4	990	/* queue was already existent, append the new entry to the end */
nandgate	0:6dee052a3fa4	991	struct etharp_q_entry *r;
nandgate	0:6dee052a3fa4	992	r = arp_table[i].q;
nandgate	0:6dee052a3fa4	993	while (r->next != NULL) {
nandgate	0:6dee052a3fa4	994	r = r->next;
nandgate	0:6dee052a3fa4	995	}
nandgate	0:6dee052a3fa4	996	r->next = new_entry;
nandgate	0:6dee052a3fa4	997	} else {
nandgate	0:6dee052a3fa4	998	/* queue did not exist, first item in queue */
nandgate	0:6dee052a3fa4	999	arp_table[i].q = new_entry;
nandgate	0:6dee052a3fa4	1000	}
nandgate	0:6dee052a3fa4	1001	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: queued packet %p on ARP entry %"S16_F"\n", (void *)q, (s16_t)i));
nandgate	0:6dee052a3fa4	1002	result = ERR_OK;
nandgate	0:6dee052a3fa4	1003	} else {
nandgate	0:6dee052a3fa4	1004	/* the pool MEMP_ARP_QUEUE is empty */
nandgate	0:6dee052a3fa4	1005	pbuf_free(p);
nandgate	0:6dee052a3fa4	1006	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));
nandgate	0:6dee052a3fa4	1007	/* { result == ERR_MEM } through initialization */
nandgate	0:6dee052a3fa4	1008	}
nandgate	0:6dee052a3fa4	1009	} else {
nandgate	0:6dee052a3fa4	1010	ETHARP_STATS_INC(etharp.memerr);
nandgate	0:6dee052a3fa4	1011	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));
nandgate	0:6dee052a3fa4	1012	/* { result == ERR_MEM } through initialization */
nandgate	0:6dee052a3fa4	1013	}
nandgate	0:6dee052a3fa4	1014	#else /* ARP_QUEUEING == 0 */
nandgate	0:6dee052a3fa4	1015	/* q && state == PENDING && ARP_QUEUEING == 0 => result = ERR_MEM */
nandgate	0:6dee052a3fa4	1016	/* { result == ERR_MEM } through initialization */
nandgate	0:6dee052a3fa4	1017	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: Ethernet destination address unknown, queueing disabled, packet %p dropped\n", (void *)q));
nandgate	0:6dee052a3fa4	1018	#endif
nandgate	0:6dee052a3fa4	1019	}
nandgate	0:6dee052a3fa4	1020	}
nandgate	0:6dee052a3fa4	1021	return result;
nandgate	0:6dee052a3fa4	1022	}
nandgate	0:6dee052a3fa4	1023
nandgate	0:6dee052a3fa4	1024	/**
nandgate	0:6dee052a3fa4	1025	* Send a raw ARP packet (opcode and all addresses can be modified)
nandgate	0:6dee052a3fa4	1026	*
nandgate	0:6dee052a3fa4	1027	* @param netif the lwip network interface on which to send the ARP packet
nandgate	0:6dee052a3fa4	1028	* @param ethsrc_addr the source MAC address for the ethernet header
nandgate	0:6dee052a3fa4	1029	* @param ethdst_addr the destination MAC address for the ethernet header
nandgate	0:6dee052a3fa4	1030	* @param hwsrc_addr the source MAC address for the ARP protocol header
nandgate	0:6dee052a3fa4	1031	* @param ipsrc_addr the source IP address for the ARP protocol header
nandgate	0:6dee052a3fa4	1032	* @param hwdst_addr the destination MAC address for the ARP protocol header
nandgate	0:6dee052a3fa4	1033	* @param ipdst_addr the destination IP address for the ARP protocol header
nandgate	0:6dee052a3fa4	1034	* @param opcode the type of the ARP packet
nandgate	0:6dee052a3fa4	1035	* @return ERR_OK if the ARP packet has been sent
nandgate	0:6dee052a3fa4	1036	* ERR_MEM if the ARP packet couldn't be allocated
nandgate	0:6dee052a3fa4	1037	* any other err_t on failure
nandgate	0:6dee052a3fa4	1038	*/
nandgate	0:6dee052a3fa4	1039	#if !LWIP_AUTOIP
nandgate	0:6dee052a3fa4	1040	static
nandgate	0:6dee052a3fa4	1041	#endif /* LWIP_AUTOIP */
nandgate	0:6dee052a3fa4	1042	err_t
nandgate	0:6dee052a3fa4	1043	etharp_raw(struct netif netif, const struct eth_addr ethsrc_addr,
nandgate	0:6dee052a3fa4	1044	const struct eth_addr *ethdst_addr,
nandgate	0:6dee052a3fa4	1045	const struct eth_addr hwsrc_addr, const struct ip_addr ipsrc_addr,
nandgate	0:6dee052a3fa4	1046	const struct eth_addr hwdst_addr, const struct ip_addr ipdst_addr,
nandgate	0:6dee052a3fa4	1047	const u16_t opcode)
nandgate	0:6dee052a3fa4	1048	{
nandgate	0:6dee052a3fa4	1049	struct pbuf *p;
nandgate	0:6dee052a3fa4	1050	err_t result = ERR_OK;
nandgate	0:6dee052a3fa4	1051	u8_t k; /* ARP entry index */
nandgate	0:6dee052a3fa4	1052	struct eth_hdr *ethhdr;
nandgate	0:6dee052a3fa4	1053	struct etharp_hdr *hdr;
nandgate	0:6dee052a3fa4	1054	#if LWIP_AUTOIP
nandgate	0:6dee052a3fa4	1055	const u8_t * ethdst_hwaddr;
nandgate	0:6dee052a3fa4	1056	#endif /* LWIP_AUTOIP */
nandgate	0:6dee052a3fa4	1057
nandgate	0:6dee052a3fa4	1058	/* allocate a pbuf for the outgoing ARP request packet */
nandgate	0:6dee052a3fa4	1059	p = pbuf_alloc(PBUF_RAW, SIZEOF_ETHARP_PACKET, PBUF_RAM);
nandgate	0:6dee052a3fa4	1060	/* could allocate a pbuf for an ARP request? */
nandgate	0:6dee052a3fa4	1061	if (p == NULL) {
nandgate	0:6dee052a3fa4	1062	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| 2, ("etharp_raw: could not allocate pbuf for ARP request.\n"));
nandgate	0:6dee052a3fa4	1063	ETHARP_STATS_INC(etharp.memerr);
nandgate	0:6dee052a3fa4	1064	return ERR_MEM;
nandgate	0:6dee052a3fa4	1065	}
nandgate	0:6dee052a3fa4	1066	LWIP_ASSERT("check that first pbuf can hold struct etharp_hdr",
nandgate	0:6dee052a3fa4	1067	(p->len >= SIZEOF_ETHARP_PACKET));
nandgate	0:6dee052a3fa4	1068
nandgate	0:6dee052a3fa4	1069	ethhdr = (struct eth_hdr *)p->payload;
nandgate	0:6dee052a3fa4	1070	hdr = (struct etharp_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
nandgate	0:6dee052a3fa4	1071	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_raw: sending raw ARP packet.\n"));
nandgate	0:6dee052a3fa4	1072	hdr->opcode = htons(opcode);
nandgate	0:6dee052a3fa4	1073
nandgate	0:6dee052a3fa4	1074	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
nandgate	0:6dee052a3fa4	1075	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
nandgate	0:6dee052a3fa4	1076	k = ETHARP_HWADDR_LEN;
nandgate	0:6dee052a3fa4	1077	#if LWIP_AUTOIP
nandgate	0:6dee052a3fa4	1078	/* If we are using Link-Local, ARP packets must be broadcast on the
nandgate	0:6dee052a3fa4	1079	* link layer. (See RFC3927 Section 2.5) */
nandgate	0:6dee052a3fa4	1080	ethdst_hwaddr = ((netif->autoip != NULL) && (netif->autoip->state != AUTOIP_STATE_OFF)) ? (u8_t*)(ethbroadcast.addr) : ethdst_addr->addr;
nandgate	0:6dee052a3fa4	1081	#endif /* LWIP_AUTOIP */
nandgate	0:6dee052a3fa4	1082	/* Write MAC-Addresses (combined loop for both headers) */
nandgate	0:6dee052a3fa4	1083	while(k > 0) {
nandgate	0:6dee052a3fa4	1084	k--;
nandgate	0:6dee052a3fa4	1085	/* Write the ARP MAC-Addresses */
nandgate	0:6dee052a3fa4	1086	hdr->shwaddr.addr[k] = hwsrc_addr->addr[k];
nandgate	0:6dee052a3fa4	1087	hdr->dhwaddr.addr[k] = hwdst_addr->addr[k];
nandgate	0:6dee052a3fa4	1088	/* Write the Ethernet MAC-Addresses */
nandgate	0:6dee052a3fa4	1089	#if LWIP_AUTOIP
nandgate	0:6dee052a3fa4	1090	ethhdr->dest.addr[k] = ethdst_hwaddr[k];
nandgate	0:6dee052a3fa4	1091	#else /* LWIP_AUTOIP */
nandgate	0:6dee052a3fa4	1092	ethhdr->dest.addr[k] = ethdst_addr->addr[k];
nandgate	0:6dee052a3fa4	1093	#endif /* LWIP_AUTOIP */
nandgate	0:6dee052a3fa4	1094	ethhdr->src.addr[k] = ethsrc_addr->addr[k];
nandgate	0:6dee052a3fa4	1095	}
nandgate	0:6dee052a3fa4	1096	hdr->sipaddr = (struct ip_addr2 )ipsrc_addr;
nandgate	0:6dee052a3fa4	1097	hdr->dipaddr = (struct ip_addr2 )ipdst_addr;
nandgate	0:6dee052a3fa4	1098
nandgate	0:6dee052a3fa4	1099	hdr->hwtype = htons(HWTYPE_ETHERNET);
nandgate	0:6dee052a3fa4	1100	hdr->proto = htons(ETHTYPE_IP);
nandgate	0:6dee052a3fa4	1101	/* set hwlen and protolen together */
nandgate	0:6dee052a3fa4	1102	hdr->_hwlen_protolen = htons((ETHARP_HWADDR_LEN << 8) \| sizeof(struct ip_addr));
nandgate	0:6dee052a3fa4	1103
nandgate	0:6dee052a3fa4	1104	ethhdr->type = htons(ETHTYPE_ARP);
nandgate	0:6dee052a3fa4	1105	/* send ARP query */
nandgate	0:6dee052a3fa4	1106	result = netif->linkoutput(netif, p);
nandgate	0:6dee052a3fa4	1107	ETHARP_STATS_INC(etharp.xmit);
nandgate	0:6dee052a3fa4	1108	/* free ARP query packet */
nandgate	0:6dee052a3fa4	1109	pbuf_free(p);
nandgate	0:6dee052a3fa4	1110	p = NULL;
nandgate	0:6dee052a3fa4	1111	/* could not allocate pbuf for ARP request */
nandgate	0:6dee052a3fa4	1112
nandgate	0:6dee052a3fa4	1113	return result;
nandgate	0:6dee052a3fa4	1114	}
nandgate	0:6dee052a3fa4	1115
nandgate	0:6dee052a3fa4	1116	/**
nandgate	0:6dee052a3fa4	1117	* Send an ARP request packet asking for ipaddr.
nandgate	0:6dee052a3fa4	1118	*
nandgate	0:6dee052a3fa4	1119	* @param netif the lwip network interface on which to send the request
nandgate	0:6dee052a3fa4	1120	* @param ipaddr the IP address for which to ask
nandgate	0:6dee052a3fa4	1121	* @return ERR_OK if the request has been sent
nandgate	0:6dee052a3fa4	1122	* ERR_MEM if the ARP packet couldn't be allocated
nandgate	0:6dee052a3fa4	1123	* any other err_t on failure
nandgate	0:6dee052a3fa4	1124	*/
nandgate	0:6dee052a3fa4	1125	err_t
nandgate	0:6dee052a3fa4	1126	etharp_request(struct netif netif, struct ip_addr ipaddr)
nandgate	0:6dee052a3fa4	1127	{
nandgate	0:6dee052a3fa4	1128	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_request: sending ARP request.\n"));
nandgate	0:6dee052a3fa4	1129	return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, &ethbroadcast,
nandgate	0:6dee052a3fa4	1130	(struct eth_addr *)netif->hwaddr, &netif->ip_addr, &ethzero,
nandgate	0:6dee052a3fa4	1131	ipaddr, ARP_REQUEST);
nandgate	0:6dee052a3fa4	1132	}
nandgate	0:6dee052a3fa4	1133
nandgate	0:6dee052a3fa4	1134	/**
nandgate	0:6dee052a3fa4	1135	* Process received ethernet frames. Using this function instead of directly
nandgate	0:6dee052a3fa4	1136	* calling ip_input and passing ARP frames through etharp in ethernetif_input,
nandgate	0:6dee052a3fa4	1137	* the ARP cache is protected from concurrent access.
nandgate	0:6dee052a3fa4	1138	*
nandgate	0:6dee052a3fa4	1139	* @param p the recevied packet, p->payload pointing to the ethernet header
nandgate	0:6dee052a3fa4	1140	* @param netif the network interface on which the packet was received
nandgate	0:6dee052a3fa4	1141	*/
nandgate	0:6dee052a3fa4	1142	err_t
nandgate	0:6dee052a3fa4	1143	ethernet_input(struct pbuf p, struct netif netif)
nandgate	0:6dee052a3fa4	1144	{
nandgate	0:6dee052a3fa4	1145	struct eth_hdr* ethhdr;
nandgate	0:6dee052a3fa4	1146	u16_t type;
nandgate	0:6dee052a3fa4	1147
nandgate	0:6dee052a3fa4	1148	/* points to packet payload, which starts with an Ethernet header */
nandgate	0:6dee052a3fa4	1149	ethhdr = (struct eth_hdr *)p->payload;
nandgate	0:6dee052a3fa4	1150	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE,
nandgate	0:6dee052a3fa4	1151	("ethernet_input: dest:%02x:%02x:%02x:%02x:%02x:%02x, src:%02x:%02x:%02x:%02x:%02x:%02x, type:%2hx\n",
nandgate	0:6dee052a3fa4	1152	(unsigned)ethhdr->dest.addr[0], (unsigned)ethhdr->dest.addr[1], (unsigned)ethhdr->dest.addr[2],
nandgate	0:6dee052a3fa4	1153	(unsigned)ethhdr->dest.addr[3], (unsigned)ethhdr->dest.addr[4], (unsigned)ethhdr->dest.addr[5],
nandgate	0:6dee052a3fa4	1154	(unsigned)ethhdr->src.addr[0], (unsigned)ethhdr->src.addr[1], (unsigned)ethhdr->src.addr[2],
nandgate	0:6dee052a3fa4	1155	(unsigned)ethhdr->src.addr[3], (unsigned)ethhdr->src.addr[4], (unsigned)ethhdr->src.addr[5],
nandgate	0:6dee052a3fa4	1156	(unsigned)htons(ethhdr->type)));
nandgate	0:6dee052a3fa4	1157
nandgate	0:6dee052a3fa4	1158	type = htons(ethhdr->type);
nandgate	0:6dee052a3fa4	1159	#if ETHARP_SUPPORT_VLAN
nandgate	0:6dee052a3fa4	1160	if (type == ETHTYPE_VLAN) {
nandgate	0:6dee052a3fa4	1161	struct eth_vlan_hdr vlan = (struct eth_vlan_hdr)(((char*)ethhdr) + SIZEOF_ETH_HDR);
nandgate	0:6dee052a3fa4	1162	#ifdef ETHARP_VLAN_CHECK /* if not, allow all VLANs */
nandgate	0:6dee052a3fa4	1163	if (VLAN_ID(vlan) != ETHARP_VLAN_CHECK) {
nandgate	0:6dee052a3fa4	1164	/* silently ignore this packet: not for our VLAN */
nandgate	0:6dee052a3fa4	1165	pbuf_free(p);
nandgate	0:6dee052a3fa4	1166	return ERR_OK;
nandgate	0:6dee052a3fa4	1167	}
nandgate	0:6dee052a3fa4	1168	#endif /* ETHARP_VLAN_CHECK */
nandgate	0:6dee052a3fa4	1169	type = htons(vlan->tpid);
nandgate	0:6dee052a3fa4	1170	}
nandgate	0:6dee052a3fa4	1171	#endif /* ETHARP_SUPPORT_VLAN */
nandgate	0:6dee052a3fa4	1172
nandgate	0:6dee052a3fa4	1173	switch (type) {
nandgate	0:6dee052a3fa4	1174	/* IP packet? */
nandgate	0:6dee052a3fa4	1175	case ETHTYPE_IP:
nandgate	0:6dee052a3fa4	1176	#if ETHARP_TRUST_IP_MAC
nandgate	0:6dee052a3fa4	1177	/* update ARP table */
nandgate	0:6dee052a3fa4	1178	etharp_ip_input(netif, p);
nandgate	0:6dee052a3fa4	1179	#endif /* ETHARP_TRUST_IP_MAC */
nandgate	0:6dee052a3fa4	1180	/* skip Ethernet header */
nandgate	0:6dee052a3fa4	1181	if(pbuf_header(p, -(s16_t)SIZEOF_ETH_HDR)) {
nandgate	0:6dee052a3fa4	1182	LWIP_ASSERT("Can't move over header in packet", 0);
nandgate	0:6dee052a3fa4	1183	pbuf_free(p);
nandgate	0:6dee052a3fa4	1184	p = NULL;
nandgate	0:6dee052a3fa4	1185	} else {
nandgate	0:6dee052a3fa4	1186	/* pass to IP layer */
nandgate	0:6dee052a3fa4	1187	ip_input(p, netif);
nandgate	0:6dee052a3fa4	1188	}
nandgate	0:6dee052a3fa4	1189	break;
nandgate	0:6dee052a3fa4	1190
nandgate	0:6dee052a3fa4	1191	case ETHTYPE_ARP:
nandgate	0:6dee052a3fa4	1192	/* pass p to ARP module */
nandgate	0:6dee052a3fa4	1193	etharp_arp_input(netif, (struct eth_addr*)(netif->hwaddr), p);
nandgate	0:6dee052a3fa4	1194	break;
nandgate	0:6dee052a3fa4	1195
nandgate	0:6dee052a3fa4	1196	#if PPPOE_SUPPORT
nandgate	0:6dee052a3fa4	1197	case ETHTYPE_PPPOEDISC: /* PPP Over Ethernet Discovery Stage */
nandgate	0:6dee052a3fa4	1198	pppoe_disc_input(netif, p);
nandgate	0:6dee052a3fa4	1199	break;
nandgate	0:6dee052a3fa4	1200
nandgate	0:6dee052a3fa4	1201	case ETHTYPE_PPPOE: /* PPP Over Ethernet Session Stage */
nandgate	0:6dee052a3fa4	1202	pppoe_data_input(netif, p);
nandgate	0:6dee052a3fa4	1203	break;
nandgate	0:6dee052a3fa4	1204	#endif /* PPPOE_SUPPORT */
nandgate	0:6dee052a3fa4	1205
nandgate	0:6dee052a3fa4	1206	default:
nandgate	0:6dee052a3fa4	1207	ETHARP_STATS_INC(etharp.proterr);
nandgate	0:6dee052a3fa4	1208	ETHARP_STATS_INC(etharp.drop);
nandgate	0:6dee052a3fa4	1209	pbuf_free(p);
nandgate	0:6dee052a3fa4	1210	p = NULL;
nandgate	0:6dee052a3fa4	1211	break;
nandgate	0:6dee052a3fa4	1212	}
nandgate	0:6dee052a3fa4	1213
nandgate	0:6dee052a3fa4	1214	/* This means the pbuf is freed or consumed,
nandgate	0:6dee052a3fa4	1215	so the caller doesn't have to free it again */
nandgate	0:6dee052a3fa4	1216	return ERR_OK;
nandgate	0:6dee052a3fa4	1217	}
nandgate	0:6dee052a3fa4	1218	#endif /* LWIP_ARP */

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	26 Jul 2011
Imports:	159
Forks:	0
Commits:	1
Dependents:	0
Dependencies:	2
Followers:	9

Core/lwIP/netif/etharp.c@0:6dee052a3fa4, 2011-07-26 (annotated)

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