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NetServices/lwip/netif/etharp.c@0:4edb816d21e1, 2015-10-16 (annotated)

Committer:: ICTFBI
Date:: Fri Oct 16 14:28:26 2015 +0000
Revision:: 0:4edb816d21e1

Pre-update 16-10-15

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User	Revision	Line number	New contents of line
ICTFBI	0:4edb816d21e1	1	/**
ICTFBI	0:4edb816d21e1	2	* @file
ICTFBI	0:4edb816d21e1	3	* Address Resolution Protocol module for IP over Ethernet
ICTFBI	0:4edb816d21e1	4	*
ICTFBI	0:4edb816d21e1	5	* Functionally, ARP is divided into two parts. The first maps an IP address
ICTFBI	0:4edb816d21e1	6	* to a physical address when sending a packet, and the second part answers
ICTFBI	0:4edb816d21e1	7	* requests from other machines for our physical address.
ICTFBI	0:4edb816d21e1	8	*
ICTFBI	0:4edb816d21e1	9	* This implementation complies with RFC 826 (Ethernet ARP). It supports
ICTFBI	0:4edb816d21e1	10	* Gratuitious ARP from RFC3220 (IP Mobility Support for IPv4) section 4.6
ICTFBI	0:4edb816d21e1	11	* if an interface calls etharp_gratuitous(our_netif) upon address change.
ICTFBI	0:4edb816d21e1	12	*/
ICTFBI	0:4edb816d21e1	13
ICTFBI	0:4edb816d21e1	14	/*
ICTFBI	0:4edb816d21e1	15	* Copyright (c) 2001-2003 Swedish Institute of Computer Science.
ICTFBI	0:4edb816d21e1	16	* Copyright (c) 2003-2004 Leon Woestenberg <leon.woestenberg@axon.tv>
ICTFBI	0:4edb816d21e1	17	* Copyright (c) 2003-2004 Axon Digital Design B.V., The Netherlands.
ICTFBI	0:4edb816d21e1	18	* All rights reserved.
ICTFBI	0:4edb816d21e1	19	*
ICTFBI	0:4edb816d21e1	20	* Redistribution and use in source and binary forms, with or without modification,
ICTFBI	0:4edb816d21e1	21	* are permitted provided that the following conditions are met:
ICTFBI	0:4edb816d21e1	22	*
ICTFBI	0:4edb816d21e1	23	* 1. Redistributions of source code must retain the above copyright notice,
ICTFBI	0:4edb816d21e1	24	* this list of conditions and the following disclaimer.
ICTFBI	0:4edb816d21e1	25	* 2. Redistributions in binary form must reproduce the above copyright notice,
ICTFBI	0:4edb816d21e1	26	* this list of conditions and the following disclaimer in the documentation
ICTFBI	0:4edb816d21e1	27	* and/or other materials provided with the distribution.
ICTFBI	0:4edb816d21e1	28	* 3. The name of the author may not be used to endorse or promote products
ICTFBI	0:4edb816d21e1	29	* derived from this software without specific prior written permission.
ICTFBI	0:4edb816d21e1	30	*
ICTFBI	0:4edb816d21e1	31	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
ICTFBI	0:4edb816d21e1	32	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
ICTFBI	0:4edb816d21e1	33	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
ICTFBI	0:4edb816d21e1	34	* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
ICTFBI	0:4edb816d21e1	35	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
ICTFBI	0:4edb816d21e1	36	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
ICTFBI	0:4edb816d21e1	37	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
ICTFBI	0:4edb816d21e1	38	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
ICTFBI	0:4edb816d21e1	39	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
ICTFBI	0:4edb816d21e1	40	* OF SUCH DAMAGE.
ICTFBI	0:4edb816d21e1	41	*
ICTFBI	0:4edb816d21e1	42	* This file is part of the lwIP TCP/IP stack.
ICTFBI	0:4edb816d21e1	43	*
ICTFBI	0:4edb816d21e1	44	*/
ICTFBI	0:4edb816d21e1	45
ICTFBI	0:4edb816d21e1	46	#include "lwip/opt.h"
ICTFBI	0:4edb816d21e1	47
ICTFBI	0:4edb816d21e1	48	#if LWIP_ARP \|\| LWIP_ETHERNET
ICTFBI	0:4edb816d21e1	49
ICTFBI	0:4edb816d21e1	50	#include "lwip/ip_addr.h"
ICTFBI	0:4edb816d21e1	51	#include "lwip/def.h"
ICTFBI	0:4edb816d21e1	52	#include "lwip/ip.h"
ICTFBI	0:4edb816d21e1	53	#include "lwip/stats.h"
ICTFBI	0:4edb816d21e1	54	#include "lwip/snmp.h"
ICTFBI	0:4edb816d21e1	55	#include "lwip/dhcp.h"
ICTFBI	0:4edb816d21e1	56	#include "lwip/autoip.h"
ICTFBI	0:4edb816d21e1	57	#include "netif/etharp.h"
ICTFBI	0:4edb816d21e1	58
ICTFBI	0:4edb816d21e1	59	#if PPPOE_SUPPORT
ICTFBI	0:4edb816d21e1	60	#include "netif/ppp_oe.h"
ICTFBI	0:4edb816d21e1	61	#endif /* PPPOE_SUPPORT */
ICTFBI	0:4edb816d21e1	62
ICTFBI	0:4edb816d21e1	63	#include <string.h>
ICTFBI	0:4edb816d21e1	64
ICTFBI	0:4edb816d21e1	65	const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}};
ICTFBI	0:4edb816d21e1	66	const struct eth_addr ethzero = {{0,0,0,0,0,0}};
ICTFBI	0:4edb816d21e1	67
ICTFBI	0:4edb816d21e1	68	#if LWIP_ARP /* don't build if not configured for use in lwipopts.h */
ICTFBI	0:4edb816d21e1	69
ICTFBI	0:4edb816d21e1	70	/** the time an ARP entry stays valid after its last update,
ICTFBI	0:4edb816d21e1	71	* for ARP_TMR_INTERVAL = 5000, this is
ICTFBI	0:4edb816d21e1	72	* (240 * 5) seconds = 20 minutes.
ICTFBI	0:4edb816d21e1	73	*/
ICTFBI	0:4edb816d21e1	74	#define ARP_MAXAGE 240
ICTFBI	0:4edb816d21e1	75	/** the time an ARP entry stays pending after first request,
ICTFBI	0:4edb816d21e1	76	* for ARP_TMR_INTERVAL = 5000, this is
ICTFBI	0:4edb816d21e1	77	* (2 * 5) seconds = 10 seconds.
ICTFBI	0:4edb816d21e1	78	*
ICTFBI	0:4edb816d21e1	79	* @internal Keep this number at least 2, otherwise it might
ICTFBI	0:4edb816d21e1	80	* run out instantly if the timeout occurs directly after a request.
ICTFBI	0:4edb816d21e1	81	*/
ICTFBI	0:4edb816d21e1	82	#define ARP_MAXPENDING 2
ICTFBI	0:4edb816d21e1	83
ICTFBI	0:4edb816d21e1	84	#define HWTYPE_ETHERNET 1
ICTFBI	0:4edb816d21e1	85
ICTFBI	0:4edb816d21e1	86	enum etharp_state {
ICTFBI	0:4edb816d21e1	87	ETHARP_STATE_EMPTY = 0,
ICTFBI	0:4edb816d21e1	88	ETHARP_STATE_PENDING,
ICTFBI	0:4edb816d21e1	89	ETHARP_STATE_STABLE
ICTFBI	0:4edb816d21e1	90	};
ICTFBI	0:4edb816d21e1	91
ICTFBI	0:4edb816d21e1	92	struct etharp_entry {
ICTFBI	0:4edb816d21e1	93	#if ARP_QUEUEING
ICTFBI	0:4edb816d21e1	94	/** Pointer to queue of pending outgoing packets on this ARP entry. */
ICTFBI	0:4edb816d21e1	95	struct etharp_q_entry *q;
ICTFBI	0:4edb816d21e1	96	#endif /* ARP_QUEUEING */
ICTFBI	0:4edb816d21e1	97	ip_addr_t ipaddr;
ICTFBI	0:4edb816d21e1	98	struct eth_addr ethaddr;
ICTFBI	0:4edb816d21e1	99	#if LWIP_SNMP
ICTFBI	0:4edb816d21e1	100	struct netif *netif;
ICTFBI	0:4edb816d21e1	101	#endif /* LWIP_SNMP */
ICTFBI	0:4edb816d21e1	102	u8_t state;
ICTFBI	0:4edb816d21e1	103	u8_t ctime;
ICTFBI	0:4edb816d21e1	104	#if ETHARP_SUPPORT_STATIC_ENTRIES
ICTFBI	0:4edb816d21e1	105	u8_t static_entry;
ICTFBI	0:4edb816d21e1	106	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
ICTFBI	0:4edb816d21e1	107	};
ICTFBI	0:4edb816d21e1	108
ICTFBI	0:4edb816d21e1	109	static struct etharp_entry arp_table[ARP_TABLE_SIZE];
ICTFBI	0:4edb816d21e1	110
ICTFBI	0:4edb816d21e1	111	#if !LWIP_NETIF_HWADDRHINT
ICTFBI	0:4edb816d21e1	112	static u8_t etharp_cached_entry;
ICTFBI	0:4edb816d21e1	113	#endif /* !LWIP_NETIF_HWADDRHINT */
ICTFBI	0:4edb816d21e1	114
ICTFBI	0:4edb816d21e1	115	/** Try hard to create a new entry - we want the IP address to appear in
ICTFBI	0:4edb816d21e1	116	the cache (even if this means removing an active entry or so). */
ICTFBI	0:4edb816d21e1	117	#define ETHARP_FLAG_TRY_HARD 1
ICTFBI	0:4edb816d21e1	118	#define ETHARP_FLAG_FIND_ONLY 2
ICTFBI	0:4edb816d21e1	119	#define ETHARP_FLAG_STATIC_ENTRY 4
ICTFBI	0:4edb816d21e1	120
ICTFBI	0:4edb816d21e1	121	#if LWIP_NETIF_HWADDRHINT
ICTFBI	0:4edb816d21e1	122	#define ETHARP_SET_HINT(netif, hint) if (((netif) != NULL) && ((netif)->addr_hint != NULL)) \
ICTFBI	0:4edb816d21e1	123	*((netif)->addr_hint) = (hint);
ICTFBI	0:4edb816d21e1	124	#else /* LWIP_NETIF_HWADDRHINT */
ICTFBI	0:4edb816d21e1	125	#define ETHARP_SET_HINT(netif, hint) (etharp_cached_entry = (hint))
ICTFBI	0:4edb816d21e1	126	#endif /* LWIP_NETIF_HWADDRHINT */
ICTFBI	0:4edb816d21e1	127
ICTFBI	0:4edb816d21e1	128	static err_t update_arp_entry(struct netif netif, ip_addr_t ipaddr, struct eth_addr *ethaddr, u8_t flags);
ICTFBI	0:4edb816d21e1	129
ICTFBI	0:4edb816d21e1	130
ICTFBI	0:4edb816d21e1	131	/* Some checks, instead of etharp_init(): */
ICTFBI	0:4edb816d21e1	132	#if (LWIP_ARP && (ARP_TABLE_SIZE > 0x7f))
ICTFBI	0:4edb816d21e1	133	#error "ARP_TABLE_SIZE must fit in an s8_t, you have to reduce it in your lwipopts.h"
ICTFBI	0:4edb816d21e1	134	#endif
ICTFBI	0:4edb816d21e1	135
ICTFBI	0:4edb816d21e1	136
ICTFBI	0:4edb816d21e1	137	#if ARP_QUEUEING
ICTFBI	0:4edb816d21e1	138	/**
ICTFBI	0:4edb816d21e1	139	* Free a complete queue of etharp entries
ICTFBI	0:4edb816d21e1	140	*
ICTFBI	0:4edb816d21e1	141	* @param q a qeueue of etharp_q_entry's to free
ICTFBI	0:4edb816d21e1	142	*/
ICTFBI	0:4edb816d21e1	143	static void
ICTFBI	0:4edb816d21e1	144	free_etharp_q(struct etharp_q_entry *q)
ICTFBI	0:4edb816d21e1	145	{
ICTFBI	0:4edb816d21e1	146	struct etharp_q_entry *r;
ICTFBI	0:4edb816d21e1	147	LWIP_ASSERT("q != NULL", q != NULL);
ICTFBI	0:4edb816d21e1	148	LWIP_ASSERT("q->p != NULL", q->p != NULL);
ICTFBI	0:4edb816d21e1	149	while (q) {
ICTFBI	0:4edb816d21e1	150	r = q;
ICTFBI	0:4edb816d21e1	151	q = q->next;
ICTFBI	0:4edb816d21e1	152	LWIP_ASSERT("r->p != NULL", (r->p != NULL));
ICTFBI	0:4edb816d21e1	153	pbuf_free(r->p);
ICTFBI	0:4edb816d21e1	154	memp_free(MEMP_ARP_QUEUE, r);
ICTFBI	0:4edb816d21e1	155	}
ICTFBI	0:4edb816d21e1	156	}
ICTFBI	0:4edb816d21e1	157	#endif /* ARP_QUEUEING */
ICTFBI	0:4edb816d21e1	158
ICTFBI	0:4edb816d21e1	159	/** Clean up ARP table entries */
ICTFBI	0:4edb816d21e1	160	static void
ICTFBI	0:4edb816d21e1	161	free_entry(int i)
ICTFBI	0:4edb816d21e1	162	{
ICTFBI	0:4edb816d21e1	163	/* remove from SNMP ARP index tree */
ICTFBI	0:4edb816d21e1	164	snmp_delete_arpidx_tree(arp_table[i].netif, &arp_table[i].ipaddr);
ICTFBI	0:4edb816d21e1	165	#if ARP_QUEUEING
ICTFBI	0:4edb816d21e1	166	/* and empty packet queue */
ICTFBI	0:4edb816d21e1	167	if (arp_table[i].q != NULL) {
ICTFBI	0:4edb816d21e1	168	/* remove all queued packets */
ICTFBI	0:4edb816d21e1	169	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: freeing entry %"U16_F", packet queue %p.\n", (u16_t)i, (void *)(arp_table[i].q)));
ICTFBI	0:4edb816d21e1	170	free_etharp_q(arp_table[i].q);
ICTFBI	0:4edb816d21e1	171	arp_table[i].q = NULL;
ICTFBI	0:4edb816d21e1	172	}
ICTFBI	0:4edb816d21e1	173	#endif /* ARP_QUEUEING */
ICTFBI	0:4edb816d21e1	174	/* recycle entry for re-use */
ICTFBI	0:4edb816d21e1	175	arp_table[i].state = ETHARP_STATE_EMPTY;
ICTFBI	0:4edb816d21e1	176	#if ETHARP_SUPPORT_STATIC_ENTRIES
ICTFBI	0:4edb816d21e1	177	arp_table[i].static_entry = 0;
ICTFBI	0:4edb816d21e1	178	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
ICTFBI	0:4edb816d21e1	179	#ifdef LWIP_DEBUG
ICTFBI	0:4edb816d21e1	180	/* for debugging, clean out the complete entry */
ICTFBI	0:4edb816d21e1	181	arp_table[i].ctime = 0;
ICTFBI	0:4edb816d21e1	182	#if LWIP_SNMP
ICTFBI	0:4edb816d21e1	183	arp_table[i].netif = NULL;
ICTFBI	0:4edb816d21e1	184	#endif /* LWIP_SNMP */
ICTFBI	0:4edb816d21e1	185	ip_addr_set_zero(&arp_table[i].ipaddr);
ICTFBI	0:4edb816d21e1	186	arp_table[i].ethaddr = ethzero;
ICTFBI	0:4edb816d21e1	187	#endif /* LWIP_DEBUG */
ICTFBI	0:4edb816d21e1	188	}
ICTFBI	0:4edb816d21e1	189
ICTFBI	0:4edb816d21e1	190	/**
ICTFBI	0:4edb816d21e1	191	* Clears expired entries in the ARP table.
ICTFBI	0:4edb816d21e1	192	*
ICTFBI	0:4edb816d21e1	193	* This function should be called every ETHARP_TMR_INTERVAL milliseconds (5 seconds),
ICTFBI	0:4edb816d21e1	194	* in order to expire entries in the ARP table.
ICTFBI	0:4edb816d21e1	195	*/
ICTFBI	0:4edb816d21e1	196	void
ICTFBI	0:4edb816d21e1	197	etharp_tmr(void)
ICTFBI	0:4edb816d21e1	198	{
ICTFBI	0:4edb816d21e1	199	u8_t i;
ICTFBI	0:4edb816d21e1	200
ICTFBI	0:4edb816d21e1	201	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer\n"));
ICTFBI	0:4edb816d21e1	202	/* remove expired entries from the ARP table */
ICTFBI	0:4edb816d21e1	203	for (i = 0; i < ARP_TABLE_SIZE; ++i) {
ICTFBI	0:4edb816d21e1	204	u8_t state = arp_table[i].state;
ICTFBI	0:4edb816d21e1	205	if (state != ETHARP_STATE_EMPTY
ICTFBI	0:4edb816d21e1	206	#if ETHARP_SUPPORT_STATIC_ENTRIES
ICTFBI	0:4edb816d21e1	207	&& (arp_table[i].static_entry == 0)
ICTFBI	0:4edb816d21e1	208	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
ICTFBI	0:4edb816d21e1	209	) {
ICTFBI	0:4edb816d21e1	210	arp_table[i].ctime++;
ICTFBI	0:4edb816d21e1	211	if ((arp_table[i].ctime >= ARP_MAXAGE) \|\|
ICTFBI	0:4edb816d21e1	212	((arp_table[i].state == ETHARP_STATE_PENDING) &&
ICTFBI	0:4edb816d21e1	213	(arp_table[i].ctime >= ARP_MAXPENDING))) {
ICTFBI	0:4edb816d21e1	214	/* pending or stable entry has become old! */
ICTFBI	0:4edb816d21e1	215	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: expired %s entry %"U16_F".\n",
ICTFBI	0:4edb816d21e1	216	arp_table[i].state == ETHARP_STATE_STABLE ? "stable" : "pending", (u16_t)i));
ICTFBI	0:4edb816d21e1	217	/* clean up entries that have just been expired */
ICTFBI	0:4edb816d21e1	218	free_entry(i);
ICTFBI	0:4edb816d21e1	219	}
ICTFBI	0:4edb816d21e1	220	#if ARP_QUEUEING
ICTFBI	0:4edb816d21e1	221	/* still pending entry? (not expired) */
ICTFBI	0:4edb816d21e1	222	if (arp_table[i].state == ETHARP_STATE_PENDING) {
ICTFBI	0:4edb816d21e1	223	/* resend an ARP query here? */
ICTFBI	0:4edb816d21e1	224	}
ICTFBI	0:4edb816d21e1	225	#endif /* ARP_QUEUEING */
ICTFBI	0:4edb816d21e1	226	}
ICTFBI	0:4edb816d21e1	227	}
ICTFBI	0:4edb816d21e1	228	}
ICTFBI	0:4edb816d21e1	229
ICTFBI	0:4edb816d21e1	230	/**
ICTFBI	0:4edb816d21e1	231	* Search the ARP table for a matching or new entry.
ICTFBI	0:4edb816d21e1	232	*
ICTFBI	0:4edb816d21e1	233	* If an IP address is given, return a pending or stable ARP entry that matches
ICTFBI	0:4edb816d21e1	234	* the address. If no match is found, create a new entry with this address set,
ICTFBI	0:4edb816d21e1	235	* but in state ETHARP_EMPTY. The caller must check and possibly change the
ICTFBI	0:4edb816d21e1	236	* state of the returned entry.
ICTFBI	0:4edb816d21e1	237	*
ICTFBI	0:4edb816d21e1	238	* If ipaddr is NULL, return a initialized new entry in state ETHARP_EMPTY.
ICTFBI	0:4edb816d21e1	239	*
ICTFBI	0:4edb816d21e1	240	* In all cases, attempt to create new entries from an empty entry. If no
ICTFBI	0:4edb816d21e1	241	* empty entries are available and ETHARP_FLAG_TRY_HARD flag is set, recycle
ICTFBI	0:4edb816d21e1	242	* old entries. Heuristic choose the least important entry for recycling.
ICTFBI	0:4edb816d21e1	243	*
ICTFBI	0:4edb816d21e1	244	* @param ipaddr IP address to find in ARP cache, or to add if not found.
ICTFBI	0:4edb816d21e1	245	* @param flags @see definition of ETHARP_FLAG_*
ICTFBI	0:4edb816d21e1	246	* @param netif netif related to this address (used for NETIF_HWADDRHINT)
ICTFBI	0:4edb816d21e1	247	*
ICTFBI	0:4edb816d21e1	248	* @return The ARP entry index that matched or is created, ERR_MEM if no
ICTFBI	0:4edb816d21e1	249	* entry is found or could be recycled.
ICTFBI	0:4edb816d21e1	250	*/
ICTFBI	0:4edb816d21e1	251	static s8_t
ICTFBI	0:4edb816d21e1	252	find_entry(ip_addr_t *ipaddr, u8_t flags)
ICTFBI	0:4edb816d21e1	253	{
ICTFBI	0:4edb816d21e1	254	s8_t old_pending = ARP_TABLE_SIZE, old_stable = ARP_TABLE_SIZE;
ICTFBI	0:4edb816d21e1	255	s8_t empty = ARP_TABLE_SIZE;
ICTFBI	0:4edb816d21e1	256	u8_t i = 0, age_pending = 0, age_stable = 0;
ICTFBI	0:4edb816d21e1	257	#if ARP_QUEUEING
ICTFBI	0:4edb816d21e1	258	/* oldest entry with packets on queue */
ICTFBI	0:4edb816d21e1	259	s8_t old_queue = ARP_TABLE_SIZE;
ICTFBI	0:4edb816d21e1	260	/* its age */
ICTFBI	0:4edb816d21e1	261	u8_t age_queue = 0;
ICTFBI	0:4edb816d21e1	262	#endif /* ARP_QUEUEING */
ICTFBI	0:4edb816d21e1	263
ICTFBI	0:4edb816d21e1	264	/**
ICTFBI	0:4edb816d21e1	265	* a) do a search through the cache, remember candidates
ICTFBI	0:4edb816d21e1	266	* b) select candidate entry
ICTFBI	0:4edb816d21e1	267	* c) create new entry
ICTFBI	0:4edb816d21e1	268	*/
ICTFBI	0:4edb816d21e1	269
ICTFBI	0:4edb816d21e1	270	/* a) in a single search sweep, do all of this
ICTFBI	0:4edb816d21e1	271	* 1) remember the first empty entry (if any)
ICTFBI	0:4edb816d21e1	272	* 2) remember the oldest stable entry (if any)
ICTFBI	0:4edb816d21e1	273	* 3) remember the oldest pending entry without queued packets (if any)
ICTFBI	0:4edb816d21e1	274	* 4) remember the oldest pending entry with queued packets (if any)
ICTFBI	0:4edb816d21e1	275	* 5) search for a matching IP entry, either pending or stable
ICTFBI	0:4edb816d21e1	276	* until 5 matches, or all entries are searched for.
ICTFBI	0:4edb816d21e1	277	*/
ICTFBI	0:4edb816d21e1	278
ICTFBI	0:4edb816d21e1	279	for (i = 0; i < ARP_TABLE_SIZE; ++i) {
ICTFBI	0:4edb816d21e1	280	u8_t state = arp_table[i].state;
ICTFBI	0:4edb816d21e1	281	/* no empty entry found yet and now we do find one? */
ICTFBI	0:4edb816d21e1	282	if ((empty == ARP_TABLE_SIZE) && (state == ETHARP_STATE_EMPTY)) {
ICTFBI	0:4edb816d21e1	283	LWIP_DEBUGF(ETHARP_DEBUG, ("find_entry: found empty entry %"U16_F"\n", (u16_t)i));
ICTFBI	0:4edb816d21e1	284	/* remember first empty entry */
ICTFBI	0:4edb816d21e1	285	empty = i;
ICTFBI	0:4edb816d21e1	286	} else if (state != ETHARP_STATE_EMPTY) {
ICTFBI	0:4edb816d21e1	287	LWIP_ASSERT("state == ETHARP_STATE_PENDING \|\| state == ETHARP_STATE_STABLE",
ICTFBI	0:4edb816d21e1	288	state == ETHARP_STATE_PENDING \|\| state == ETHARP_STATE_STABLE);
ICTFBI	0:4edb816d21e1	289	/* if given, does IP address match IP address in ARP entry? */
ICTFBI	0:4edb816d21e1	290	if (ipaddr && ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
ICTFBI	0:4edb816d21e1	291	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: found matching entry %"U16_F"\n", (u16_t)i));
ICTFBI	0:4edb816d21e1	292	/* found exact IP address match, simply bail out */
ICTFBI	0:4edb816d21e1	293	return i;
ICTFBI	0:4edb816d21e1	294	}
ICTFBI	0:4edb816d21e1	295	/* pending entry? */
ICTFBI	0:4edb816d21e1	296	if (state == ETHARP_STATE_PENDING) {
ICTFBI	0:4edb816d21e1	297	/* pending with queued packets? */
ICTFBI	0:4edb816d21e1	298	#if ARP_QUEUEING
ICTFBI	0:4edb816d21e1	299	if (arp_table[i].q != NULL) {
ICTFBI	0:4edb816d21e1	300	if (arp_table[i].ctime >= age_queue) {
ICTFBI	0:4edb816d21e1	301	old_queue = i;
ICTFBI	0:4edb816d21e1	302	age_queue = arp_table[i].ctime;
ICTFBI	0:4edb816d21e1	303	}
ICTFBI	0:4edb816d21e1	304	} else
ICTFBI	0:4edb816d21e1	305	#endif /* ARP_QUEUEING */
ICTFBI	0:4edb816d21e1	306	/* pending without queued packets? */
ICTFBI	0:4edb816d21e1	307	{
ICTFBI	0:4edb816d21e1	308	if (arp_table[i].ctime >= age_pending) {
ICTFBI	0:4edb816d21e1	309	old_pending = i;
ICTFBI	0:4edb816d21e1	310	age_pending = arp_table[i].ctime;
ICTFBI	0:4edb816d21e1	311	}
ICTFBI	0:4edb816d21e1	312	}
ICTFBI	0:4edb816d21e1	313	/* stable entry? */
ICTFBI	0:4edb816d21e1	314	} else if (state == ETHARP_STATE_STABLE) {
ICTFBI	0:4edb816d21e1	315	#if ETHARP_SUPPORT_STATIC_ENTRIES
ICTFBI	0:4edb816d21e1	316	/* don't record old_stable for static entries since they never expire */
ICTFBI	0:4edb816d21e1	317	if (arp_table[i].static_entry == 0)
ICTFBI	0:4edb816d21e1	318	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
ICTFBI	0:4edb816d21e1	319	{
ICTFBI	0:4edb816d21e1	320	/* remember entry with oldest stable entry in oldest, its age in maxtime */
ICTFBI	0:4edb816d21e1	321	if (arp_table[i].ctime >= age_stable) {
ICTFBI	0:4edb816d21e1	322	old_stable = i;
ICTFBI	0:4edb816d21e1	323	age_stable = arp_table[i].ctime;
ICTFBI	0:4edb816d21e1	324	}
ICTFBI	0:4edb816d21e1	325	}
ICTFBI	0:4edb816d21e1	326	}
ICTFBI	0:4edb816d21e1	327	}
ICTFBI	0:4edb816d21e1	328	}
ICTFBI	0:4edb816d21e1	329	/* { we have no match } => try to create a new entry */
ICTFBI	0:4edb816d21e1	330
ICTFBI	0:4edb816d21e1	331	/* don't create new entry, only search? */
ICTFBI	0:4edb816d21e1	332	if (((flags & ETHARP_FLAG_FIND_ONLY) != 0) \|\|
ICTFBI	0:4edb816d21e1	333	/* or no empty entry found and not allowed to recycle? */
ICTFBI	0:4edb816d21e1	334	((empty == ARP_TABLE_SIZE) && ((flags & ETHARP_FLAG_TRY_HARD) == 0))) {
ICTFBI	0:4edb816d21e1	335	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: no empty entry found and not allowed to recycle\n"));
ICTFBI	0:4edb816d21e1	336	return (s8_t)ERR_MEM;
ICTFBI	0:4edb816d21e1	337	}
ICTFBI	0:4edb816d21e1	338
ICTFBI	0:4edb816d21e1	339	/* b) choose the least destructive entry to recycle:
ICTFBI	0:4edb816d21e1	340	* 1) empty entry
ICTFBI	0:4edb816d21e1	341	* 2) oldest stable entry
ICTFBI	0:4edb816d21e1	342	* 3) oldest pending entry without queued packets
ICTFBI	0:4edb816d21e1	343	* 4) oldest pending entry with queued packets
ICTFBI	0:4edb816d21e1	344	*
ICTFBI	0:4edb816d21e1	345	* { ETHARP_FLAG_TRY_HARD is set at this point }
ICTFBI	0:4edb816d21e1	346	*/
ICTFBI	0:4edb816d21e1	347
ICTFBI	0:4edb816d21e1	348	/* 1) empty entry available? */
ICTFBI	0:4edb816d21e1	349	if (empty < ARP_TABLE_SIZE) {
ICTFBI	0:4edb816d21e1	350	i = empty;
ICTFBI	0:4edb816d21e1	351	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting empty entry %"U16_F"\n", (u16_t)i));
ICTFBI	0:4edb816d21e1	352	} else {
ICTFBI	0:4edb816d21e1	353	/* 2) found recyclable stable entry? */
ICTFBI	0:4edb816d21e1	354	if (old_stable < ARP_TABLE_SIZE) {
ICTFBI	0:4edb816d21e1	355	/* recycle oldest stable*/
ICTFBI	0:4edb816d21e1	356	i = old_stable;
ICTFBI	0:4edb816d21e1	357	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest stable entry %"U16_F"\n", (u16_t)i));
ICTFBI	0:4edb816d21e1	358	#if ARP_QUEUEING
ICTFBI	0:4edb816d21e1	359	/* no queued packets should exist on stable entries */
ICTFBI	0:4edb816d21e1	360	LWIP_ASSERT("arp_table[i].q == NULL", arp_table[i].q == NULL);
ICTFBI	0:4edb816d21e1	361	#endif /* ARP_QUEUEING */
ICTFBI	0:4edb816d21e1	362	/* 3) found recyclable pending entry without queued packets? */
ICTFBI	0:4edb816d21e1	363	} else if (old_pending < ARP_TABLE_SIZE) {
ICTFBI	0:4edb816d21e1	364	/* recycle oldest pending */
ICTFBI	0:4edb816d21e1	365	i = old_pending;
ICTFBI	0:4edb816d21e1	366	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest pending entry %"U16_F" (without queue)\n", (u16_t)i));
ICTFBI	0:4edb816d21e1	367	#if ARP_QUEUEING
ICTFBI	0:4edb816d21e1	368	/* 4) found recyclable pending entry with queued packets? */
ICTFBI	0:4edb816d21e1	369	} else if (old_queue < ARP_TABLE_SIZE) {
ICTFBI	0:4edb816d21e1	370	/* recycle oldest pending (queued packets are free in free_entry) */
ICTFBI	0:4edb816d21e1	371	i = old_queue;
ICTFBI	0:4edb816d21e1	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)));
ICTFBI	0:4edb816d21e1	373	#endif /* ARP_QUEUEING */
ICTFBI	0:4edb816d21e1	374	/* no empty or recyclable entries found */
ICTFBI	0:4edb816d21e1	375	} else {
ICTFBI	0:4edb816d21e1	376	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: no empty or recyclable entries found\n"));
ICTFBI	0:4edb816d21e1	377	return (s8_t)ERR_MEM;
ICTFBI	0:4edb816d21e1	378	}
ICTFBI	0:4edb816d21e1	379
ICTFBI	0:4edb816d21e1	380	/* { empty or recyclable entry found } */
ICTFBI	0:4edb816d21e1	381	LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
ICTFBI	0:4edb816d21e1	382	free_entry(i);
ICTFBI	0:4edb816d21e1	383	}
ICTFBI	0:4edb816d21e1	384
ICTFBI	0:4edb816d21e1	385	LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
ICTFBI	0:4edb816d21e1	386	LWIP_ASSERT("arp_table[i].state == ETHARP_STATE_EMPTY",
ICTFBI	0:4edb816d21e1	387	arp_table[i].state == ETHARP_STATE_EMPTY);
ICTFBI	0:4edb816d21e1	388
ICTFBI	0:4edb816d21e1	389	/* IP address given? */
ICTFBI	0:4edb816d21e1	390	if (ipaddr != NULL) {
ICTFBI	0:4edb816d21e1	391	/* set IP address */
ICTFBI	0:4edb816d21e1	392	ip_addr_copy(arp_table[i].ipaddr, *ipaddr);
ICTFBI	0:4edb816d21e1	393	}
ICTFBI	0:4edb816d21e1	394	arp_table[i].ctime = 0;
ICTFBI	0:4edb816d21e1	395	#if ETHARP_SUPPORT_STATIC_ENTRIES
ICTFBI	0:4edb816d21e1	396	arp_table[i].static_entry = 0;
ICTFBI	0:4edb816d21e1	397	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
ICTFBI	0:4edb816d21e1	398	return (err_t)i;
ICTFBI	0:4edb816d21e1	399	}
ICTFBI	0:4edb816d21e1	400
ICTFBI	0:4edb816d21e1	401	/**
ICTFBI	0:4edb816d21e1	402	* Send an IP packet on the network using netif->linkoutput
ICTFBI	0:4edb816d21e1	403	* The ethernet header is filled in before sending.
ICTFBI	0:4edb816d21e1	404	*
ICTFBI	0:4edb816d21e1	405	* @params netif the lwIP network interface on which to send the packet
ICTFBI	0:4edb816d21e1	406	* @params p the packet to send, p->payload pointing to the (uninitialized) ethernet header
ICTFBI	0:4edb816d21e1	407	* @params src the source MAC address to be copied into the ethernet header
ICTFBI	0:4edb816d21e1	408	* @params dst the destination MAC address to be copied into the ethernet header
ICTFBI	0:4edb816d21e1	409	* @return ERR_OK if the packet was sent, any other err_t on failure
ICTFBI	0:4edb816d21e1	410	*/
ICTFBI	0:4edb816d21e1	411	static err_t
ICTFBI	0:4edb816d21e1	412	etharp_send_ip(struct netif netif, struct pbuf p, struct eth_addr src, struct eth_addr dst)
ICTFBI	0:4edb816d21e1	413	{
ICTFBI	0:4edb816d21e1	414	struct eth_hdr ethhdr = (struct eth_hdr )p->payload;
ICTFBI	0:4edb816d21e1	415
ICTFBI	0:4edb816d21e1	416	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
ICTFBI	0:4edb816d21e1	417	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
ICTFBI	0:4edb816d21e1	418	ETHADDR32_COPY(&ethhdr->dest, dst);
ICTFBI	0:4edb816d21e1	419	ETHADDR16_COPY(&ethhdr->src, src);
ICTFBI	0:4edb816d21e1	420	ethhdr->type = PP_HTONS(ETHTYPE_IP);
ICTFBI	0:4edb816d21e1	421	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_send_ip: sending packet %p\n", (void *)p));
ICTFBI	0:4edb816d21e1	422	/* send the packet */
ICTFBI	0:4edb816d21e1	423	return netif->linkoutput(netif, p);
ICTFBI	0:4edb816d21e1	424	}
ICTFBI	0:4edb816d21e1	425
ICTFBI	0:4edb816d21e1	426	/**
ICTFBI	0:4edb816d21e1	427	* Update (or insert) a IP/MAC address pair in the ARP cache.
ICTFBI	0:4edb816d21e1	428	*
ICTFBI	0:4edb816d21e1	429	* If a pending entry is resolved, any queued packets will be sent
ICTFBI	0:4edb816d21e1	430	* at this point.
ICTFBI	0:4edb816d21e1	431	*
ICTFBI	0:4edb816d21e1	432	* @param netif netif related to this entry (used for NETIF_ADDRHINT)
ICTFBI	0:4edb816d21e1	433	* @param ipaddr IP address of the inserted ARP entry.
ICTFBI	0:4edb816d21e1	434	* @param ethaddr Ethernet address of the inserted ARP entry.
ICTFBI	0:4edb816d21e1	435	* @param flags @see definition of ETHARP_FLAG_*
ICTFBI	0:4edb816d21e1	436	*
ICTFBI	0:4edb816d21e1	437	* @return
ICTFBI	0:4edb816d21e1	438	* - ERR_OK Succesfully updated ARP cache.
ICTFBI	0:4edb816d21e1	439	* - ERR_MEM If we could not add a new ARP entry when ETHARP_FLAG_TRY_HARD was set.
ICTFBI	0:4edb816d21e1	440	* - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
ICTFBI	0:4edb816d21e1	441	*
ICTFBI	0:4edb816d21e1	442	* @see pbuf_free()
ICTFBI	0:4edb816d21e1	443	*/
ICTFBI	0:4edb816d21e1	444	static err_t
ICTFBI	0:4edb816d21e1	445	update_arp_entry(struct netif netif, ip_addr_t ipaddr, struct eth_addr *ethaddr, u8_t flags)
ICTFBI	0:4edb816d21e1	446	{
ICTFBI	0:4edb816d21e1	447	s8_t i;
ICTFBI	0:4edb816d21e1	448	LWIP_ASSERT("netif->hwaddr_len == ETHARP_HWADDR_LEN", netif->hwaddr_len == ETHARP_HWADDR_LEN);
ICTFBI	0:4edb816d21e1	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",
ICTFBI	0:4edb816d21e1	450	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
ICTFBI	0:4edb816d21e1	451	ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
ICTFBI	0:4edb816d21e1	452	ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
ICTFBI	0:4edb816d21e1	453	/* non-unicast address? */
ICTFBI	0:4edb816d21e1	454	if (ip_addr_isany(ipaddr) \|\|
ICTFBI	0:4edb816d21e1	455	ip_addr_isbroadcast(ipaddr, netif) \|\|
ICTFBI	0:4edb816d21e1	456	ip_addr_ismulticast(ipaddr)) {
ICTFBI	0:4edb816d21e1	457	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: will not add non-unicast IP address to ARP cache\n"));
ICTFBI	0:4edb816d21e1	458	return ERR_ARG;
ICTFBI	0:4edb816d21e1	459	}
ICTFBI	0:4edb816d21e1	460	/* find or create ARP entry */
ICTFBI	0:4edb816d21e1	461	i = find_entry(ipaddr, flags);
ICTFBI	0:4edb816d21e1	462	/* bail out if no entry could be found */
ICTFBI	0:4edb816d21e1	463	if (i < 0) {
ICTFBI	0:4edb816d21e1	464	return (err_t)i;
ICTFBI	0:4edb816d21e1	465	}
ICTFBI	0:4edb816d21e1	466
ICTFBI	0:4edb816d21e1	467	#if ETHARP_SUPPORT_STATIC_ENTRIES
ICTFBI	0:4edb816d21e1	468	if (flags & ETHARP_FLAG_STATIC_ENTRY) {
ICTFBI	0:4edb816d21e1	469	/* record static type */
ICTFBI	0:4edb816d21e1	470	arp_table[i].static_entry = 1;
ICTFBI	0:4edb816d21e1	471	}
ICTFBI	0:4edb816d21e1	472	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
ICTFBI	0:4edb816d21e1	473
ICTFBI	0:4edb816d21e1	474	/* mark it stable */
ICTFBI	0:4edb816d21e1	475	arp_table[i].state = ETHARP_STATE_STABLE;
ICTFBI	0:4edb816d21e1	476
ICTFBI	0:4edb816d21e1	477	#if LWIP_SNMP
ICTFBI	0:4edb816d21e1	478	/* record network interface */
ICTFBI	0:4edb816d21e1	479	arp_table[i].netif = netif;
ICTFBI	0:4edb816d21e1	480	#endif /* LWIP_SNMP */
ICTFBI	0:4edb816d21e1	481	/* insert in SNMP ARP index tree */
ICTFBI	0:4edb816d21e1	482	snmp_insert_arpidx_tree(netif, &arp_table[i].ipaddr);
ICTFBI	0:4edb816d21e1	483
ICTFBI	0:4edb816d21e1	484	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: updating stable entry %"S16_F"\n", (s16_t)i));
ICTFBI	0:4edb816d21e1	485	/* update address */
ICTFBI	0:4edb816d21e1	486	ETHADDR32_COPY(&arp_table[i].ethaddr, ethaddr);
ICTFBI	0:4edb816d21e1	487	/* reset time stamp */
ICTFBI	0:4edb816d21e1	488	arp_table[i].ctime = 0;
ICTFBI	0:4edb816d21e1	489	#if ARP_QUEUEING
ICTFBI	0:4edb816d21e1	490	/* this is where we will send out queued packets! */
ICTFBI	0:4edb816d21e1	491	while (arp_table[i].q != NULL) {
ICTFBI	0:4edb816d21e1	492	struct pbuf *p;
ICTFBI	0:4edb816d21e1	493	/* remember remainder of queue */
ICTFBI	0:4edb816d21e1	494	struct etharp_q_entry *q = arp_table[i].q;
ICTFBI	0:4edb816d21e1	495	/* pop first item off the queue */
ICTFBI	0:4edb816d21e1	496	arp_table[i].q = q->next;
ICTFBI	0:4edb816d21e1	497	/* get the packet pointer */
ICTFBI	0:4edb816d21e1	498	p = q->p;
ICTFBI	0:4edb816d21e1	499	/* now queue entry can be freed */
ICTFBI	0:4edb816d21e1	500	memp_free(MEMP_ARP_QUEUE, q);
ICTFBI	0:4edb816d21e1	501	/* send the queued IP packet */
ICTFBI	0:4edb816d21e1	502	etharp_send_ip(netif, p, (struct eth_addr*)(netif->hwaddr), ethaddr);
ICTFBI	0:4edb816d21e1	503	/* free the queued IP packet */
ICTFBI	0:4edb816d21e1	504	pbuf_free(p);
ICTFBI	0:4edb816d21e1	505	}
ICTFBI	0:4edb816d21e1	506	#endif /* ARP_QUEUEING */
ICTFBI	0:4edb816d21e1	507	return ERR_OK;
ICTFBI	0:4edb816d21e1	508	}
ICTFBI	0:4edb816d21e1	509
ICTFBI	0:4edb816d21e1	510	#if ETHARP_SUPPORT_STATIC_ENTRIES
ICTFBI	0:4edb816d21e1	511	/** Add a new static entry to the ARP table. If an entry exists for the
ICTFBI	0:4edb816d21e1	512	* specified IP address, this entry is overwritten.
ICTFBI	0:4edb816d21e1	513	* If packets are queued for the specified IP address, they are sent out.
ICTFBI	0:4edb816d21e1	514	*
ICTFBI	0:4edb816d21e1	515	* @param ipaddr IP address for the new static entry
ICTFBI	0:4edb816d21e1	516	* @param ethaddr ethernet address for the new static entry
ICTFBI	0:4edb816d21e1	517	* @return @see return values of etharp_add_static_entry
ICTFBI	0:4edb816d21e1	518	*/
ICTFBI	0:4edb816d21e1	519	err_t
ICTFBI	0:4edb816d21e1	520	etharp_add_static_entry(ip_addr_t ipaddr, struct eth_addr ethaddr)
ICTFBI	0:4edb816d21e1	521	{
ICTFBI	0:4edb816d21e1	522	struct netif *netif;
ICTFBI	0:4edb816d21e1	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",
ICTFBI	0:4edb816d21e1	524	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
ICTFBI	0:4edb816d21e1	525	ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
ICTFBI	0:4edb816d21e1	526	ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
ICTFBI	0:4edb816d21e1	527
ICTFBI	0:4edb816d21e1	528	netif = ip_route(ipaddr);
ICTFBI	0:4edb816d21e1	529	if (netif == NULL) {
ICTFBI	0:4edb816d21e1	530	return ERR_RTE;
ICTFBI	0:4edb816d21e1	531	}
ICTFBI	0:4edb816d21e1	532
ICTFBI	0:4edb816d21e1	533	return update_arp_entry(netif, ipaddr, ethaddr, ETHARP_FLAG_TRY_HARD \| ETHARP_FLAG_STATIC_ENTRY);
ICTFBI	0:4edb816d21e1	534	}
ICTFBI	0:4edb816d21e1	535
ICTFBI	0:4edb816d21e1	536	/** Remove a static entry from the ARP table previously added with a call to
ICTFBI	0:4edb816d21e1	537	* etharp_add_static_entry.
ICTFBI	0:4edb816d21e1	538	*
ICTFBI	0:4edb816d21e1	539	* @param ipaddr IP address of the static entry to remove
ICTFBI	0:4edb816d21e1	540	* @return ERR_OK: entry removed
ICTFBI	0:4edb816d21e1	541	* ERR_MEM: entry wasn't found
ICTFBI	0:4edb816d21e1	542	* ERR_ARG: entry wasn't a static entry but a dynamic one
ICTFBI	0:4edb816d21e1	543	*/
ICTFBI	0:4edb816d21e1	544	err_t
ICTFBI	0:4edb816d21e1	545	etharp_remove_static_entry(ip_addr_t *ipaddr)
ICTFBI	0:4edb816d21e1	546	{
ICTFBI	0:4edb816d21e1	547	s8_t i;
ICTFBI	0:4edb816d21e1	548	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_remove_static_entry: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
ICTFBI	0:4edb816d21e1	549	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr)));
ICTFBI	0:4edb816d21e1	550
ICTFBI	0:4edb816d21e1	551	/* find or create ARP entry */
ICTFBI	0:4edb816d21e1	552	i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
ICTFBI	0:4edb816d21e1	553	/* bail out if no entry could be found */
ICTFBI	0:4edb816d21e1	554	if (i < 0) {
ICTFBI	0:4edb816d21e1	555	return (err_t)i;
ICTFBI	0:4edb816d21e1	556	}
ICTFBI	0:4edb816d21e1	557
ICTFBI	0:4edb816d21e1	558	if ((arp_table[i].state != ETHARP_STATE_STABLE) \|\|
ICTFBI	0:4edb816d21e1	559	(arp_table[i].static_entry == 0)) {
ICTFBI	0:4edb816d21e1	560	/* entry wasn't a static entry, cannot remove it */
ICTFBI	0:4edb816d21e1	561	return ERR_ARG;
ICTFBI	0:4edb816d21e1	562	}
ICTFBI	0:4edb816d21e1	563	/* entry found, free it */
ICTFBI	0:4edb816d21e1	564	free_entry(i);
ICTFBI	0:4edb816d21e1	565	return ERR_OK;
ICTFBI	0:4edb816d21e1	566	}
ICTFBI	0:4edb816d21e1	567	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
ICTFBI	0:4edb816d21e1	568
ICTFBI	0:4edb816d21e1	569	/**
ICTFBI	0:4edb816d21e1	570	* Finds (stable) ethernet/IP address pair from ARP table
ICTFBI	0:4edb816d21e1	571	* using interface and IP address index.
ICTFBI	0:4edb816d21e1	572	* @note the addresses in the ARP table are in network order!
ICTFBI	0:4edb816d21e1	573	*
ICTFBI	0:4edb816d21e1	574	* @param netif points to interface index
ICTFBI	0:4edb816d21e1	575	* @param ipaddr points to the (network order) IP address index
ICTFBI	0:4edb816d21e1	576	* @param eth_ret points to return pointer
ICTFBI	0:4edb816d21e1	577	* @param ip_ret points to return pointer
ICTFBI	0:4edb816d21e1	578	* @return table index if found, -1 otherwise
ICTFBI	0:4edb816d21e1	579	*/
ICTFBI	0:4edb816d21e1	580	s8_t
ICTFBI	0:4edb816d21e1	581	etharp_find_addr(struct netif netif, ip_addr_t ipaddr,
ICTFBI	0:4edb816d21e1	582	struct eth_addr eth_ret, ip_addr_t ip_ret)
ICTFBI	0:4edb816d21e1	583	{
ICTFBI	0:4edb816d21e1	584	s8_t i;
ICTFBI	0:4edb816d21e1	585
ICTFBI	0:4edb816d21e1	586	LWIP_ASSERT("eth_ret != NULL && ip_ret != NULL",
ICTFBI	0:4edb816d21e1	587	eth_ret != NULL && ip_ret != NULL);
ICTFBI	0:4edb816d21e1	588
ICTFBI	0:4edb816d21e1	589	LWIP_UNUSED_ARG(netif);
ICTFBI	0:4edb816d21e1	590
ICTFBI	0:4edb816d21e1	591	i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
ICTFBI	0:4edb816d21e1	592	if((i >= 0) && arp_table[i].state == ETHARP_STATE_STABLE) {
ICTFBI	0:4edb816d21e1	593	*eth_ret = &arp_table[i].ethaddr;
ICTFBI	0:4edb816d21e1	594	*ip_ret = &arp_table[i].ipaddr;
ICTFBI	0:4edb816d21e1	595	return i;
ICTFBI	0:4edb816d21e1	596	}
ICTFBI	0:4edb816d21e1	597	return -1;
ICTFBI	0:4edb816d21e1	598	}
ICTFBI	0:4edb816d21e1	599
ICTFBI	0:4edb816d21e1	600	#if ETHARP_TRUST_IP_MAC
ICTFBI	0:4edb816d21e1	601	/**
ICTFBI	0:4edb816d21e1	602	* Updates the ARP table using the given IP packet.
ICTFBI	0:4edb816d21e1	603	*
ICTFBI	0:4edb816d21e1	604	* Uses the incoming IP packet's source address to update the
ICTFBI	0:4edb816d21e1	605	* ARP cache for the local network. The function does not alter
ICTFBI	0:4edb816d21e1	606	* or free the packet. This function must be called before the
ICTFBI	0:4edb816d21e1	607	* packet p is passed to the IP layer.
ICTFBI	0:4edb816d21e1	608	*
ICTFBI	0:4edb816d21e1	609	* @param netif The lwIP network interface on which the IP packet pbuf arrived.
ICTFBI	0:4edb816d21e1	610	* @param p The IP packet that arrived on netif.
ICTFBI	0:4edb816d21e1	611	*
ICTFBI	0:4edb816d21e1	612	* @return NULL
ICTFBI	0:4edb816d21e1	613	*
ICTFBI	0:4edb816d21e1	614	* @see pbuf_free()
ICTFBI	0:4edb816d21e1	615	*/
ICTFBI	0:4edb816d21e1	616	static void
ICTFBI	0:4edb816d21e1	617	etharp_ip_input(struct netif netif, struct pbuf p)
ICTFBI	0:4edb816d21e1	618	{
ICTFBI	0:4edb816d21e1	619	struct eth_hdr *ethhdr;
ICTFBI	0:4edb816d21e1	620	struct ip_hdr *iphdr;
ICTFBI	0:4edb816d21e1	621	ip_addr_t iphdr_src;
ICTFBI	0:4edb816d21e1	622	LWIP_ERROR("netif != NULL", (netif != NULL), return;);
ICTFBI	0:4edb816d21e1	623
ICTFBI	0:4edb816d21e1	624	/* Only insert an entry if the source IP address of the
ICTFBI	0:4edb816d21e1	625	incoming IP packet comes from a host on the local network. */
ICTFBI	0:4edb816d21e1	626	ethhdr = (struct eth_hdr *)p->payload;
ICTFBI	0:4edb816d21e1	627	iphdr = (struct ip_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
ICTFBI	0:4edb816d21e1	628	#if ETHARP_SUPPORT_VLAN
ICTFBI	0:4edb816d21e1	629	if (ethhdr->type == ETHTYPE_VLAN) {
ICTFBI	0:4edb816d21e1	630	iphdr = (struct ip_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
ICTFBI	0:4edb816d21e1	631	}
ICTFBI	0:4edb816d21e1	632	#endif /* ETHARP_SUPPORT_VLAN */
ICTFBI	0:4edb816d21e1	633
ICTFBI	0:4edb816d21e1	634	ip_addr_copy(iphdr_src, iphdr->src);
ICTFBI	0:4edb816d21e1	635
ICTFBI	0:4edb816d21e1	636	/* source is not on the local network? */
ICTFBI	0:4edb816d21e1	637	if (!ip_addr_netcmp(&iphdr_src, &(netif->ip_addr), &(netif->netmask))) {
ICTFBI	0:4edb816d21e1	638	/* do nothing */
ICTFBI	0:4edb816d21e1	639	return;
ICTFBI	0:4edb816d21e1	640	}
ICTFBI	0:4edb816d21e1	641
ICTFBI	0:4edb816d21e1	642	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_ip_input: updating ETHARP table.\n"));
ICTFBI	0:4edb816d21e1	643	/* update the source IP address in the cache, if present */
ICTFBI	0:4edb816d21e1	644	/* @todo We could use ETHARP_FLAG_TRY_HARD if we think we are going to talk
ICTFBI	0:4edb816d21e1	645	* back soon (for example, if the destination IP address is ours. */
ICTFBI	0:4edb816d21e1	646	update_arp_entry(netif, &iphdr_src, &(ethhdr->src), ETHARP_FLAG_FIND_ONLY);
ICTFBI	0:4edb816d21e1	647	}
ICTFBI	0:4edb816d21e1	648	#endif /* ETHARP_TRUST_IP_MAC */
ICTFBI	0:4edb816d21e1	649
ICTFBI	0:4edb816d21e1	650	/**
ICTFBI	0:4edb816d21e1	651	* Responds to ARP requests to us. Upon ARP replies to us, add entry to cache
ICTFBI	0:4edb816d21e1	652	* send out queued IP packets. Updates cache with snooped address pairs.
ICTFBI	0:4edb816d21e1	653	*
ICTFBI	0:4edb816d21e1	654	* Should be called for incoming ARP packets. The pbuf in the argument
ICTFBI	0:4edb816d21e1	655	* is freed by this function.
ICTFBI	0:4edb816d21e1	656	*
ICTFBI	0:4edb816d21e1	657	* @param netif The lwIP network interface on which the ARP packet pbuf arrived.
ICTFBI	0:4edb816d21e1	658	* @param ethaddr Ethernet address of netif.
ICTFBI	0:4edb816d21e1	659	* @param p The ARP packet that arrived on netif. Is freed by this function.
ICTFBI	0:4edb816d21e1	660	*
ICTFBI	0:4edb816d21e1	661	* @return NULL
ICTFBI	0:4edb816d21e1	662	*
ICTFBI	0:4edb816d21e1	663	* @see pbuf_free()
ICTFBI	0:4edb816d21e1	664	*/
ICTFBI	0:4edb816d21e1	665	static void
ICTFBI	0:4edb816d21e1	666	etharp_arp_input(struct netif netif, struct eth_addr ethaddr, struct pbuf *p)
ICTFBI	0:4edb816d21e1	667	{
ICTFBI	0:4edb816d21e1	668	struct etharp_hdr *hdr;
ICTFBI	0:4edb816d21e1	669	struct eth_hdr *ethhdr;
ICTFBI	0:4edb816d21e1	670	/* these are aligned properly, whereas the ARP header fields might not be */
ICTFBI	0:4edb816d21e1	671	ip_addr_t sipaddr, dipaddr;
ICTFBI	0:4edb816d21e1	672	u8_t for_us;
ICTFBI	0:4edb816d21e1	673	#if LWIP_AUTOIP
ICTFBI	0:4edb816d21e1	674	const u8_t * ethdst_hwaddr;
ICTFBI	0:4edb816d21e1	675	#endif /* LWIP_AUTOIP */
ICTFBI	0:4edb816d21e1	676
ICTFBI	0:4edb816d21e1	677	LWIP_ERROR("netif != NULL", (netif != NULL), return;);
ICTFBI	0:4edb816d21e1	678
ICTFBI	0:4edb816d21e1	679	/* drop short ARP packets: we have to check for p->len instead of p->tot_len here
ICTFBI	0:4edb816d21e1	680	since a struct etharp_hdr is pointed to p->payload, so it musn't be chained! */
ICTFBI	0:4edb816d21e1	681	if (p->len < SIZEOF_ETHARP_PACKET) {
ICTFBI	0:4edb816d21e1	682	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_WARNING,
ICTFBI	0:4edb816d21e1	683	("etharp_arp_input: packet dropped, too short (%"S16_F"/%"S16_F")\n", p->tot_len,
ICTFBI	0:4edb816d21e1	684	(s16_t)SIZEOF_ETHARP_PACKET));
ICTFBI	0:4edb816d21e1	685	ETHARP_STATS_INC(etharp.lenerr);
ICTFBI	0:4edb816d21e1	686	ETHARP_STATS_INC(etharp.drop);
ICTFBI	0:4edb816d21e1	687	pbuf_free(p);
ICTFBI	0:4edb816d21e1	688	return;
ICTFBI	0:4edb816d21e1	689	}
ICTFBI	0:4edb816d21e1	690
ICTFBI	0:4edb816d21e1	691	ethhdr = (struct eth_hdr *)p->payload;
ICTFBI	0:4edb816d21e1	692	hdr = (struct etharp_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
ICTFBI	0:4edb816d21e1	693	#if ETHARP_SUPPORT_VLAN
ICTFBI	0:4edb816d21e1	694	if (ethhdr->type == ETHTYPE_VLAN) {
ICTFBI	0:4edb816d21e1	695	hdr = (struct etharp_hdr )(((u8_t)ethhdr) + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
ICTFBI	0:4edb816d21e1	696	}
ICTFBI	0:4edb816d21e1	697	#endif /* ETHARP_SUPPORT_VLAN */
ICTFBI	0:4edb816d21e1	698
ICTFBI	0:4edb816d21e1	699	/* RFC 826 "Packet Reception": */
ICTFBI	0:4edb816d21e1	700	if ((hdr->hwtype != PP_HTONS(HWTYPE_ETHERNET)) \|\|
ICTFBI	0:4edb816d21e1	701	(hdr->hwlen != ETHARP_HWADDR_LEN) \|\|
ICTFBI	0:4edb816d21e1	702	(hdr->protolen != sizeof(ip_addr_t)) \|\|
ICTFBI	0:4edb816d21e1	703	(hdr->proto != PP_HTONS(ETHTYPE_IP)) \|\|
ICTFBI	0:4edb816d21e1	704	(ethhdr->type != PP_HTONS(ETHTYPE_ARP))) {
ICTFBI	0:4edb816d21e1	705	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_WARNING,
ICTFBI	0:4edb816d21e1	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",
ICTFBI	0:4edb816d21e1	707	hdr->hwtype, hdr->hwlen, hdr->proto, hdr->protolen, ethhdr->type));
ICTFBI	0:4edb816d21e1	708	ETHARP_STATS_INC(etharp.proterr);
ICTFBI	0:4edb816d21e1	709	ETHARP_STATS_INC(etharp.drop);
ICTFBI	0:4edb816d21e1	710	pbuf_free(p);
ICTFBI	0:4edb816d21e1	711	return;
ICTFBI	0:4edb816d21e1	712	}
ICTFBI	0:4edb816d21e1	713	ETHARP_STATS_INC(etharp.recv);
ICTFBI	0:4edb816d21e1	714
ICTFBI	0:4edb816d21e1	715	#if LWIP_AUTOIP
ICTFBI	0:4edb816d21e1	716	/* We have to check if a host already has configured our random
ICTFBI	0:4edb816d21e1	717	* created link local address and continously check if there is
ICTFBI	0:4edb816d21e1	718	* a host with this IP-address so we can detect collisions */
ICTFBI	0:4edb816d21e1	719	autoip_arp_reply(netif, hdr);
ICTFBI	0:4edb816d21e1	720	#endif /* LWIP_AUTOIP */
ICTFBI	0:4edb816d21e1	721
ICTFBI	0:4edb816d21e1	722	/* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
ICTFBI	0:4edb816d21e1	723	* structure packing (not using structure copy which breaks strict-aliasing rules). */
ICTFBI	0:4edb816d21e1	724	IPADDR2_COPY(&sipaddr, &hdr->sipaddr);
ICTFBI	0:4edb816d21e1	725	IPADDR2_COPY(&dipaddr, &hdr->dipaddr);
ICTFBI	0:4edb816d21e1	726
ICTFBI	0:4edb816d21e1	727	/* this interface is not configured? */
ICTFBI	0:4edb816d21e1	728	if (ip_addr_isany(&netif->ip_addr)) {
ICTFBI	0:4edb816d21e1	729	for_us = 0;
ICTFBI	0:4edb816d21e1	730	} else {
ICTFBI	0:4edb816d21e1	731	/* ARP packet directed to us? */
ICTFBI	0:4edb816d21e1	732	for_us = (u8_t)ip_addr_cmp(&dipaddr, &(netif->ip_addr));
ICTFBI	0:4edb816d21e1	733	}
ICTFBI	0:4edb816d21e1	734
ICTFBI	0:4edb816d21e1	735	/* ARP message directed to us?
ICTFBI	0:4edb816d21e1	736	-> add IP address in ARP cache; assume requester wants to talk to us,
ICTFBI	0:4edb816d21e1	737	can result in directly sending the queued packets for this host.
ICTFBI	0:4edb816d21e1	738	ARP message not directed to us?
ICTFBI	0:4edb816d21e1	739	-> update the source IP address in the cache, if present */
ICTFBI	0:4edb816d21e1	740	update_arp_entry(netif, &sipaddr, &(hdr->shwaddr),
ICTFBI	0:4edb816d21e1	741	for_us ? ETHARP_FLAG_TRY_HARD : ETHARP_FLAG_FIND_ONLY);
ICTFBI	0:4edb816d21e1	742
ICTFBI	0:4edb816d21e1	743	/* now act on the message itself */
ICTFBI	0:4edb816d21e1	744	switch (hdr->opcode) {
ICTFBI	0:4edb816d21e1	745	/* ARP request? */
ICTFBI	0:4edb816d21e1	746	case PP_HTONS(ARP_REQUEST):
ICTFBI	0:4edb816d21e1	747	/* ARP request. If it asked for our address, we send out a
ICTFBI	0:4edb816d21e1	748	* reply. In any case, we time-stamp any existing ARP entry,
ICTFBI	0:4edb816d21e1	749	* and possiby send out an IP packet that was queued on it. */
ICTFBI	0:4edb816d21e1	750
ICTFBI	0:4edb816d21e1	751	LWIP_DEBUGF (ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP request\n"));
ICTFBI	0:4edb816d21e1	752	/* ARP request for our address? */
ICTFBI	0:4edb816d21e1	753	if (for_us) {
ICTFBI	0:4edb816d21e1	754
ICTFBI	0:4edb816d21e1	755	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: replying to ARP request for our IP address\n"));
ICTFBI	0:4edb816d21e1	756	/* Re-use pbuf to send ARP reply.
ICTFBI	0:4edb816d21e1	757	Since we are re-using an existing pbuf, we can't call etharp_raw since
ICTFBI	0:4edb816d21e1	758	that would allocate a new pbuf. */
ICTFBI	0:4edb816d21e1	759	hdr->opcode = htons(ARP_REPLY);
ICTFBI	0:4edb816d21e1	760
ICTFBI	0:4edb816d21e1	761	IPADDR2_COPY(&hdr->dipaddr, &hdr->sipaddr);
ICTFBI	0:4edb816d21e1	762	IPADDR2_COPY(&hdr->sipaddr, &netif->ip_addr);
ICTFBI	0:4edb816d21e1	763
ICTFBI	0:4edb816d21e1	764	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
ICTFBI	0:4edb816d21e1	765	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
ICTFBI	0:4edb816d21e1	766	#if LWIP_AUTOIP
ICTFBI	0:4edb816d21e1	767	/* If we are using Link-Local, all ARP packets that contain a Link-Local
ICTFBI	0:4edb816d21e1	768	* 'sender IP address' MUST be sent using link-layer broadcast instead of
ICTFBI	0:4edb816d21e1	769	* link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
ICTFBI	0:4edb816d21e1	770	ethdst_hwaddr = ip_addr_islinklocal(&netif->ip_addr) ? (u8_t*)(ethbroadcast.addr) : hdr->shwaddr.addr;
ICTFBI	0:4edb816d21e1	771	#endif /* LWIP_AUTOIP */
ICTFBI	0:4edb816d21e1	772
ICTFBI	0:4edb816d21e1	773	ETHADDR16_COPY(&hdr->dhwaddr, &hdr->shwaddr);
ICTFBI	0:4edb816d21e1	774	#if LWIP_AUTOIP
ICTFBI	0:4edb816d21e1	775	ETHADDR16_COPY(&ethhdr->dest, ethdst_hwaddr);
ICTFBI	0:4edb816d21e1	776	#else /* LWIP_AUTOIP */
ICTFBI	0:4edb816d21e1	777	ETHADDR16_COPY(&ethhdr->dest, &hdr->shwaddr);
ICTFBI	0:4edb816d21e1	778	#endif /* LWIP_AUTOIP */
ICTFBI	0:4edb816d21e1	779	ETHADDR16_COPY(&hdr->shwaddr, ethaddr);
ICTFBI	0:4edb816d21e1	780	ETHADDR16_COPY(&ethhdr->src, ethaddr);
ICTFBI	0:4edb816d21e1	781
ICTFBI	0:4edb816d21e1	782	/* hwtype, hwaddr_len, proto, protolen and the type in the ethernet header
ICTFBI	0:4edb816d21e1	783	are already correct, we tested that before */
ICTFBI	0:4edb816d21e1	784
ICTFBI	0:4edb816d21e1	785	/* return ARP reply */
ICTFBI	0:4edb816d21e1	786	netif->linkoutput(netif, p);
ICTFBI	0:4edb816d21e1	787	/* we are not configured? */
ICTFBI	0:4edb816d21e1	788	} else if (ip_addr_isany(&netif->ip_addr)) {
ICTFBI	0:4edb816d21e1	789	/* { for_us == 0 and netif->ip_addr.addr == 0 } */
ICTFBI	0:4edb816d21e1	790	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: we are unconfigured, ARP request ignored.\n"));
ICTFBI	0:4edb816d21e1	791	/* request was not directed to us */
ICTFBI	0:4edb816d21e1	792	} else {
ICTFBI	0:4edb816d21e1	793	/* { for_us == 0 and netif->ip_addr.addr != 0 } */
ICTFBI	0:4edb816d21e1	794	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: ARP request was not for us.\n"));
ICTFBI	0:4edb816d21e1	795	}
ICTFBI	0:4edb816d21e1	796	break;
ICTFBI	0:4edb816d21e1	797	case PP_HTONS(ARP_REPLY):
ICTFBI	0:4edb816d21e1	798	/* ARP reply. We already updated the ARP cache earlier. */
ICTFBI	0:4edb816d21e1	799	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP reply\n"));
ICTFBI	0:4edb816d21e1	800	#if (LWIP_DHCP && DHCP_DOES_ARP_CHECK)
ICTFBI	0:4edb816d21e1	801	/* DHCP wants to know about ARP replies from any host with an
ICTFBI	0:4edb816d21e1	802	* IP address also offered to us by the DHCP server. We do not
ICTFBI	0:4edb816d21e1	803	* want to take a duplicate IP address on a single network.
ICTFBI	0:4edb816d21e1	804	* @todo How should we handle redundant (fail-over) interfaces? */
ICTFBI	0:4edb816d21e1	805	dhcp_arp_reply(netif, &sipaddr);
ICTFBI	0:4edb816d21e1	806	#endif /* (LWIP_DHCP && DHCP_DOES_ARP_CHECK) */
ICTFBI	0:4edb816d21e1	807	break;
ICTFBI	0:4edb816d21e1	808	default:
ICTFBI	0:4edb816d21e1	809	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: ARP unknown opcode type %"S16_F"\n", htons(hdr->opcode)));
ICTFBI	0:4edb816d21e1	810	ETHARP_STATS_INC(etharp.err);
ICTFBI	0:4edb816d21e1	811	break;
ICTFBI	0:4edb816d21e1	812	}
ICTFBI	0:4edb816d21e1	813	/* free ARP packet */
ICTFBI	0:4edb816d21e1	814	pbuf_free(p);
ICTFBI	0:4edb816d21e1	815	}
ICTFBI	0:4edb816d21e1	816
ICTFBI	0:4edb816d21e1	817	/**
ICTFBI	0:4edb816d21e1	818	* Resolve and fill-in Ethernet address header for outgoing IP packet.
ICTFBI	0:4edb816d21e1	819	*
ICTFBI	0:4edb816d21e1	820	* For IP multicast and broadcast, corresponding Ethernet addresses
ICTFBI	0:4edb816d21e1	821	* are selected and the packet is transmitted on the link.
ICTFBI	0:4edb816d21e1	822	*
ICTFBI	0:4edb816d21e1	823	* For unicast addresses, the packet is submitted to etharp_query(). In
ICTFBI	0:4edb816d21e1	824	* case the IP address is outside the local network, the IP address of
ICTFBI	0:4edb816d21e1	825	* the gateway is used.
ICTFBI	0:4edb816d21e1	826	*
ICTFBI	0:4edb816d21e1	827	* @param netif The lwIP network interface which the IP packet will be sent on.
ICTFBI	0:4edb816d21e1	828	* @param q The pbuf(s) containing the IP packet to be sent.
ICTFBI	0:4edb816d21e1	829	* @param ipaddr The IP address of the packet destination.
ICTFBI	0:4edb816d21e1	830	*
ICTFBI	0:4edb816d21e1	831	* @return
ICTFBI	0:4edb816d21e1	832	* - ERR_RTE No route to destination (no gateway to external networks),
ICTFBI	0:4edb816d21e1	833	* or the return type of either etharp_query() or etharp_send_ip().
ICTFBI	0:4edb816d21e1	834	*/
ICTFBI	0:4edb816d21e1	835	err_t
ICTFBI	0:4edb816d21e1	836	etharp_output(struct netif netif, struct pbuf q, ip_addr_t *ipaddr)
ICTFBI	0:4edb816d21e1	837	{
ICTFBI	0:4edb816d21e1	838	struct eth_addr *dest, mcastaddr;
ICTFBI	0:4edb816d21e1	839
ICTFBI	0:4edb816d21e1	840	/* make room for Ethernet header - should not fail */
ICTFBI	0:4edb816d21e1	841	if (pbuf_header(q, sizeof(struct eth_hdr)) != 0) {
ICTFBI	0:4edb816d21e1	842	/* bail out */
ICTFBI	0:4edb816d21e1	843	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_SERIOUS,
ICTFBI	0:4edb816d21e1	844	("etharp_output: could not allocate room for header.\n"));
ICTFBI	0:4edb816d21e1	845	LINK_STATS_INC(link.lenerr);
ICTFBI	0:4edb816d21e1	846	return ERR_BUF;
ICTFBI	0:4edb816d21e1	847	}
ICTFBI	0:4edb816d21e1	848
ICTFBI	0:4edb816d21e1	849	/* assume unresolved Ethernet address */
ICTFBI	0:4edb816d21e1	850	dest = NULL;
ICTFBI	0:4edb816d21e1	851	/* Determine on destination hardware address. Broadcasts and multicasts
ICTFBI	0:4edb816d21e1	852	* are special, other IP addresses are looked up in the ARP table. */
ICTFBI	0:4edb816d21e1	853
ICTFBI	0:4edb816d21e1	854	/* broadcast destination IP address? */
ICTFBI	0:4edb816d21e1	855	if (ip_addr_isbroadcast(ipaddr, netif)) {
ICTFBI	0:4edb816d21e1	856	/* broadcast on Ethernet also */
ICTFBI	0:4edb816d21e1	857	dest = (struct eth_addr *)&ethbroadcast;
ICTFBI	0:4edb816d21e1	858	/* multicast destination IP address? */
ICTFBI	0:4edb816d21e1	859	} else if (ip_addr_ismulticast(ipaddr)) {
ICTFBI	0:4edb816d21e1	860	/* Hash IP multicast address to MAC address.*/
ICTFBI	0:4edb816d21e1	861	mcastaddr.addr[0] = 0x01;
ICTFBI	0:4edb816d21e1	862	mcastaddr.addr[1] = 0x00;
ICTFBI	0:4edb816d21e1	863	mcastaddr.addr[2] = 0x5e;
ICTFBI	0:4edb816d21e1	864	mcastaddr.addr[3] = ip4_addr2(ipaddr) & 0x7f;
ICTFBI	0:4edb816d21e1	865	mcastaddr.addr[4] = ip4_addr3(ipaddr);
ICTFBI	0:4edb816d21e1	866	mcastaddr.addr[5] = ip4_addr4(ipaddr);
ICTFBI	0:4edb816d21e1	867	/* destination Ethernet address is multicast */
ICTFBI	0:4edb816d21e1	868	dest = &mcastaddr;
ICTFBI	0:4edb816d21e1	869	/* unicast destination IP address? */
ICTFBI	0:4edb816d21e1	870	} else {
ICTFBI	0:4edb816d21e1	871	/* outside local network? */
ICTFBI	0:4edb816d21e1	872	if (!ip_addr_netcmp(ipaddr, &(netif->ip_addr), &(netif->netmask)) &&
ICTFBI	0:4edb816d21e1	873	!ip_addr_islinklocal(ipaddr)) {
ICTFBI	0:4edb816d21e1	874	/* interface has default gateway? */
ICTFBI	0:4edb816d21e1	875	if (!ip_addr_isany(&netif->gw)) {
ICTFBI	0:4edb816d21e1	876	/* send to hardware address of default gateway IP address */
ICTFBI	0:4edb816d21e1	877	ipaddr = &(netif->gw);
ICTFBI	0:4edb816d21e1	878	/* no default gateway available */
ICTFBI	0:4edb816d21e1	879	} else {
ICTFBI	0:4edb816d21e1	880	/* no route to destination error (default gateway missing) */
ICTFBI	0:4edb816d21e1	881	return ERR_RTE;
ICTFBI	0:4edb816d21e1	882	}
ICTFBI	0:4edb816d21e1	883	}
ICTFBI	0:4edb816d21e1	884	#if LWIP_NETIF_HWADDRHINT
ICTFBI	0:4edb816d21e1	885	if (netif->addr_hint != NULL) {
ICTFBI	0:4edb816d21e1	886	/* per-pcb cached entry was given */
ICTFBI	0:4edb816d21e1	887	u8_t etharp_cached_entry = *(netif->addr_hint);
ICTFBI	0:4edb816d21e1	888	if (etharp_cached_entry < ARP_TABLE_SIZE) {
ICTFBI	0:4edb816d21e1	889	#endif /* LWIP_NETIF_HWADDRHINT */
ICTFBI	0:4edb816d21e1	890	if ((arp_table[etharp_cached_entry].state == ETHARP_STATE_STABLE) &&
ICTFBI	0:4edb816d21e1	891	(ip_addr_cmp(ipaddr, &arp_table[etharp_cached_entry].ipaddr))) {
ICTFBI	0:4edb816d21e1	892	/* the per-pcb-cached entry is stable and the right one! */
ICTFBI	0:4edb816d21e1	893	ETHARP_STATS_INC(etharp.cachehit);
ICTFBI	0:4edb816d21e1	894	return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr),
ICTFBI	0:4edb816d21e1	895	&arp_table[etharp_cached_entry].ethaddr);
ICTFBI	0:4edb816d21e1	896	}
ICTFBI	0:4edb816d21e1	897	#if LWIP_NETIF_HWADDRHINT
ICTFBI	0:4edb816d21e1	898	}
ICTFBI	0:4edb816d21e1	899	}
ICTFBI	0:4edb816d21e1	900	#endif /* LWIP_NETIF_HWADDRHINT */
ICTFBI	0:4edb816d21e1	901	/* queue on destination Ethernet address belonging to ipaddr */
ICTFBI	0:4edb816d21e1	902	return etharp_query(netif, ipaddr, q);
ICTFBI	0:4edb816d21e1	903	}
ICTFBI	0:4edb816d21e1	904
ICTFBI	0:4edb816d21e1	905	/* continuation for multicast/broadcast destinations */
ICTFBI	0:4edb816d21e1	906	/* obtain source Ethernet address of the given interface */
ICTFBI	0:4edb816d21e1	907	/* send packet directly on the link */
ICTFBI	0:4edb816d21e1	908	return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr), dest);
ICTFBI	0:4edb816d21e1	909	}
ICTFBI	0:4edb816d21e1	910
ICTFBI	0:4edb816d21e1	911	/**
ICTFBI	0:4edb816d21e1	912	* Send an ARP request for the given IP address and/or queue a packet.
ICTFBI	0:4edb816d21e1	913	*
ICTFBI	0:4edb816d21e1	914	* If the IP address was not yet in the cache, a pending ARP cache entry
ICTFBI	0:4edb816d21e1	915	* is added and an ARP request is sent for the given address. The packet
ICTFBI	0:4edb816d21e1	916	* is queued on this entry.
ICTFBI	0:4edb816d21e1	917	*
ICTFBI	0:4edb816d21e1	918	* If the IP address was already pending in the cache, a new ARP request
ICTFBI	0:4edb816d21e1	919	* is sent for the given address. The packet is queued on this entry.
ICTFBI	0:4edb816d21e1	920	*
ICTFBI	0:4edb816d21e1	921	* If the IP address was already stable in the cache, and a packet is
ICTFBI	0:4edb816d21e1	922	* given, it is directly sent and no ARP request is sent out.
ICTFBI	0:4edb816d21e1	923	*
ICTFBI	0:4edb816d21e1	924	* If the IP address was already stable in the cache, and no packet is
ICTFBI	0:4edb816d21e1	925	* given, an ARP request is sent out.
ICTFBI	0:4edb816d21e1	926	*
ICTFBI	0:4edb816d21e1	927	* @param netif The lwIP network interface on which ipaddr
ICTFBI	0:4edb816d21e1	928	* must be queried for.
ICTFBI	0:4edb816d21e1	929	* @param ipaddr The IP address to be resolved.
ICTFBI	0:4edb816d21e1	930	* @param q If non-NULL, a pbuf that must be delivered to the IP address.
ICTFBI	0:4edb816d21e1	931	* q is not freed by this function.
ICTFBI	0:4edb816d21e1	932	*
ICTFBI	0:4edb816d21e1	933	* @note q must only be ONE packet, not a packet queue!
ICTFBI	0:4edb816d21e1	934	*
ICTFBI	0:4edb816d21e1	935	* @return
ICTFBI	0:4edb816d21e1	936	* - ERR_BUF Could not make room for Ethernet header.
ICTFBI	0:4edb816d21e1	937	* - ERR_MEM Hardware address unknown, and no more ARP entries available
ICTFBI	0:4edb816d21e1	938	* to query for address or queue the packet.
ICTFBI	0:4edb816d21e1	939	* - ERR_MEM Could not queue packet due to memory shortage.
ICTFBI	0:4edb816d21e1	940	* - ERR_RTE No route to destination (no gateway to external networks).
ICTFBI	0:4edb816d21e1	941	* - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
ICTFBI	0:4edb816d21e1	942	*
ICTFBI	0:4edb816d21e1	943	*/
ICTFBI	0:4edb816d21e1	944	err_t
ICTFBI	0:4edb816d21e1	945	etharp_query(struct netif netif, ip_addr_t ipaddr, struct pbuf *q)
ICTFBI	0:4edb816d21e1	946	{
ICTFBI	0:4edb816d21e1	947	struct eth_addr * srcaddr = (struct eth_addr *)netif->hwaddr;
ICTFBI	0:4edb816d21e1	948	err_t result = ERR_MEM;
ICTFBI	0:4edb816d21e1	949	s8_t i; /* ARP entry index */
ICTFBI	0:4edb816d21e1	950
ICTFBI	0:4edb816d21e1	951	/* non-unicast address? */
ICTFBI	0:4edb816d21e1	952	if (ip_addr_isbroadcast(ipaddr, netif) \|\|
ICTFBI	0:4edb816d21e1	953	ip_addr_ismulticast(ipaddr) \|\|
ICTFBI	0:4edb816d21e1	954	ip_addr_isany(ipaddr)) {
ICTFBI	0:4edb816d21e1	955	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: will not add non-unicast IP address to ARP cache\n"));
ICTFBI	0:4edb816d21e1	956	return ERR_ARG;
ICTFBI	0:4edb816d21e1	957	}
ICTFBI	0:4edb816d21e1	958
ICTFBI	0:4edb816d21e1	959	/* find entry in ARP cache, ask to create entry if queueing packet */
ICTFBI	0:4edb816d21e1	960	i = find_entry(ipaddr, ETHARP_FLAG_TRY_HARD);
ICTFBI	0:4edb816d21e1	961
ICTFBI	0:4edb816d21e1	962	/* could not find or create entry? */
ICTFBI	0:4edb816d21e1	963	if (i < 0) {
ICTFBI	0:4edb816d21e1	964	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: could not create ARP entry\n"));
ICTFBI	0:4edb816d21e1	965	if (q) {
ICTFBI	0:4edb816d21e1	966	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: packet dropped\n"));
ICTFBI	0:4edb816d21e1	967	ETHARP_STATS_INC(etharp.memerr);
ICTFBI	0:4edb816d21e1	968	}
ICTFBI	0:4edb816d21e1	969	return (err_t)i;
ICTFBI	0:4edb816d21e1	970	}
ICTFBI	0:4edb816d21e1	971
ICTFBI	0:4edb816d21e1	972	/* mark a fresh entry as pending (we just sent a request) */
ICTFBI	0:4edb816d21e1	973	if (arp_table[i].state == ETHARP_STATE_EMPTY) {
ICTFBI	0:4edb816d21e1	974	arp_table[i].state = ETHARP_STATE_PENDING;
ICTFBI	0:4edb816d21e1	975	}
ICTFBI	0:4edb816d21e1	976
ICTFBI	0:4edb816d21e1	977	/* { i is either a STABLE or (new or existing) PENDING entry } */
ICTFBI	0:4edb816d21e1	978	LWIP_ASSERT("arp_table[i].state == PENDING or STABLE",
ICTFBI	0:4edb816d21e1	979	((arp_table[i].state == ETHARP_STATE_PENDING) \|\|
ICTFBI	0:4edb816d21e1	980	(arp_table[i].state == ETHARP_STATE_STABLE)));
ICTFBI	0:4edb816d21e1	981
ICTFBI	0:4edb816d21e1	982	/* do we have a pending entry? or an implicit query request? */
ICTFBI	0:4edb816d21e1	983	if ((arp_table[i].state == ETHARP_STATE_PENDING) \|\| (q == NULL)) {
ICTFBI	0:4edb816d21e1	984	/* try to resolve it; send out ARP request */
ICTFBI	0:4edb816d21e1	985	result = etharp_request(netif, ipaddr);
ICTFBI	0:4edb816d21e1	986	if (result != ERR_OK) {
ICTFBI	0:4edb816d21e1	987	/* ARP request couldn't be sent */
ICTFBI	0:4edb816d21e1	988	/* We don't re-send arp request in etharp_tmr, but we still queue packets,
ICTFBI	0:4edb816d21e1	989	since this failure could be temporary, and the next packet calling
ICTFBI	0:4edb816d21e1	990	etharp_query again could lead to sending the queued packets. */
ICTFBI	0:4edb816d21e1	991	}
ICTFBI	0:4edb816d21e1	992	if (q == NULL) {
ICTFBI	0:4edb816d21e1	993	return result;
ICTFBI	0:4edb816d21e1	994	}
ICTFBI	0:4edb816d21e1	995	}
ICTFBI	0:4edb816d21e1	996
ICTFBI	0:4edb816d21e1	997	/* packet given? */
ICTFBI	0:4edb816d21e1	998	LWIP_ASSERT("q != NULL", q != NULL);
ICTFBI	0:4edb816d21e1	999	/* stable entry? */
ICTFBI	0:4edb816d21e1	1000	if (arp_table[i].state == ETHARP_STATE_STABLE) {
ICTFBI	0:4edb816d21e1	1001	/* we have a valid IP->Ethernet address mapping */
ICTFBI	0:4edb816d21e1	1002	ETHARP_SET_HINT(netif, i);
ICTFBI	0:4edb816d21e1	1003	/* send the packet */
ICTFBI	0:4edb816d21e1	1004	result = etharp_send_ip(netif, q, srcaddr, &(arp_table[i].ethaddr));
ICTFBI	0:4edb816d21e1	1005	/* pending entry? (either just created or already pending */
ICTFBI	0:4edb816d21e1	1006	} else if (arp_table[i].state == ETHARP_STATE_PENDING) {
ICTFBI	0:4edb816d21e1	1007	#if ARP_QUEUEING /* queue the given q packet */
ICTFBI	0:4edb816d21e1	1008	struct pbuf *p;
ICTFBI	0:4edb816d21e1	1009	int copy_needed = 0;
ICTFBI	0:4edb816d21e1	1010	/* IF q includes a PBUF_REF, PBUF_POOL or PBUF_RAM, we have no choice but
ICTFBI	0:4edb816d21e1	1011	* to copy the whole queue into a new PBUF_RAM (see bug #11400)
ICTFBI	0:4edb816d21e1	1012	* PBUF_ROMs can be left as they are, since ROM must not get changed. */
ICTFBI	0:4edb816d21e1	1013	p = q;
ICTFBI	0:4edb816d21e1	1014	while (p) {
ICTFBI	0:4edb816d21e1	1015	LWIP_ASSERT("no packet queues allowed!", (p->len != p->tot_len) \|\| (p->next == 0));
ICTFBI	0:4edb816d21e1	1016	if(p->type != PBUF_ROM) {
ICTFBI	0:4edb816d21e1	1017	copy_needed = 1;
ICTFBI	0:4edb816d21e1	1018	break;
ICTFBI	0:4edb816d21e1	1019	}
ICTFBI	0:4edb816d21e1	1020	p = p->next;
ICTFBI	0:4edb816d21e1	1021	}
ICTFBI	0:4edb816d21e1	1022	if(copy_needed) {
ICTFBI	0:4edb816d21e1	1023	/* copy the whole packet into new pbufs */
ICTFBI	0:4edb816d21e1	1024	p = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
ICTFBI	0:4edb816d21e1	1025	if(p != NULL) {
ICTFBI	0:4edb816d21e1	1026	if (pbuf_copy(p, q) != ERR_OK) {
ICTFBI	0:4edb816d21e1	1027	pbuf_free(p);
ICTFBI	0:4edb816d21e1	1028	p = NULL;
ICTFBI	0:4edb816d21e1	1029	}
ICTFBI	0:4edb816d21e1	1030	}
ICTFBI	0:4edb816d21e1	1031	} else {
ICTFBI	0:4edb816d21e1	1032	/* referencing the old pbuf is enough */
ICTFBI	0:4edb816d21e1	1033	p = q;
ICTFBI	0:4edb816d21e1	1034	pbuf_ref(p);
ICTFBI	0:4edb816d21e1	1035	}
ICTFBI	0:4edb816d21e1	1036	/* packet could be taken over? */
ICTFBI	0:4edb816d21e1	1037	if (p != NULL) {
ICTFBI	0:4edb816d21e1	1038	/* queue packet ... */
ICTFBI	0:4edb816d21e1	1039	struct etharp_q_entry *new_entry;
ICTFBI	0:4edb816d21e1	1040	/* allocate a new arp queue entry */
ICTFBI	0:4edb816d21e1	1041	new_entry = (struct etharp_q_entry *)memp_malloc(MEMP_ARP_QUEUE);
ICTFBI	0:4edb816d21e1	1042	if (new_entry != NULL) {
ICTFBI	0:4edb816d21e1	1043	new_entry->next = 0;
ICTFBI	0:4edb816d21e1	1044	new_entry->p = p;
ICTFBI	0:4edb816d21e1	1045	if(arp_table[i].q != NULL) {
ICTFBI	0:4edb816d21e1	1046	/* queue was already existent, append the new entry to the end */
ICTFBI	0:4edb816d21e1	1047	struct etharp_q_entry *r;
ICTFBI	0:4edb816d21e1	1048	r = arp_table[i].q;
ICTFBI	0:4edb816d21e1	1049	while (r->next != NULL) {
ICTFBI	0:4edb816d21e1	1050	r = r->next;
ICTFBI	0:4edb816d21e1	1051	}
ICTFBI	0:4edb816d21e1	1052	r->next = new_entry;
ICTFBI	0:4edb816d21e1	1053	} else {
ICTFBI	0:4edb816d21e1	1054	/* queue did not exist, first item in queue */
ICTFBI	0:4edb816d21e1	1055	arp_table[i].q = new_entry;
ICTFBI	0:4edb816d21e1	1056	}
ICTFBI	0:4edb816d21e1	1057	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: queued packet %p on ARP entry %"S16_F"\n", (void *)q, (s16_t)i));
ICTFBI	0:4edb816d21e1	1058	result = ERR_OK;
ICTFBI	0:4edb816d21e1	1059	} else {
ICTFBI	0:4edb816d21e1	1060	/* the pool MEMP_ARP_QUEUE is empty */
ICTFBI	0:4edb816d21e1	1061	pbuf_free(p);
ICTFBI	0:4edb816d21e1	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));
ICTFBI	0:4edb816d21e1	1063	/* { result == ERR_MEM } through initialization */
ICTFBI	0:4edb816d21e1	1064	}
ICTFBI	0:4edb816d21e1	1065	} else {
ICTFBI	0:4edb816d21e1	1066	ETHARP_STATS_INC(etharp.memerr);
ICTFBI	0:4edb816d21e1	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));
ICTFBI	0:4edb816d21e1	1068	/* { result == ERR_MEM } through initialization */
ICTFBI	0:4edb816d21e1	1069	}
ICTFBI	0:4edb816d21e1	1070	#else /* ARP_QUEUEING */
ICTFBI	0:4edb816d21e1	1071	/* q && state == PENDING && ARP_QUEUEING == 0 => result = ERR_MEM */
ICTFBI	0:4edb816d21e1	1072	/* { result == ERR_MEM } through initialization */
ICTFBI	0:4edb816d21e1	1073	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: Ethernet destination address unknown, queueing disabled, packet %p dropped\n", (void *)q));
ICTFBI	0:4edb816d21e1	1074	#endif /* ARP_QUEUEING */
ICTFBI	0:4edb816d21e1	1075	}
ICTFBI	0:4edb816d21e1	1076	return result;
ICTFBI	0:4edb816d21e1	1077	}
ICTFBI	0:4edb816d21e1	1078
ICTFBI	0:4edb816d21e1	1079	/**
ICTFBI	0:4edb816d21e1	1080	* Send a raw ARP packet (opcode and all addresses can be modified)
ICTFBI	0:4edb816d21e1	1081	*
ICTFBI	0:4edb816d21e1	1082	* @param netif the lwip network interface on which to send the ARP packet
ICTFBI	0:4edb816d21e1	1083	* @param ethsrc_addr the source MAC address for the ethernet header
ICTFBI	0:4edb816d21e1	1084	* @param ethdst_addr the destination MAC address for the ethernet header
ICTFBI	0:4edb816d21e1	1085	* @param hwsrc_addr the source MAC address for the ARP protocol header
ICTFBI	0:4edb816d21e1	1086	* @param ipsrc_addr the source IP address for the ARP protocol header
ICTFBI	0:4edb816d21e1	1087	* @param hwdst_addr the destination MAC address for the ARP protocol header
ICTFBI	0:4edb816d21e1	1088	* @param ipdst_addr the destination IP address for the ARP protocol header
ICTFBI	0:4edb816d21e1	1089	* @param opcode the type of the ARP packet
ICTFBI	0:4edb816d21e1	1090	* @return ERR_OK if the ARP packet has been sent
ICTFBI	0:4edb816d21e1	1091	* ERR_MEM if the ARP packet couldn't be allocated
ICTFBI	0:4edb816d21e1	1092	* any other err_t on failure
ICTFBI	0:4edb816d21e1	1093	*/
ICTFBI	0:4edb816d21e1	1094	#if !LWIP_AUTOIP
ICTFBI	0:4edb816d21e1	1095	static
ICTFBI	0:4edb816d21e1	1096	#endif /* LWIP_AUTOIP */
ICTFBI	0:4edb816d21e1	1097	err_t
ICTFBI	0:4edb816d21e1	1098	etharp_raw(struct netif netif, const struct eth_addr ethsrc_addr,
ICTFBI	0:4edb816d21e1	1099	const struct eth_addr *ethdst_addr,
ICTFBI	0:4edb816d21e1	1100	const struct eth_addr hwsrc_addr, const ip_addr_t ipsrc_addr,
ICTFBI	0:4edb816d21e1	1101	const struct eth_addr hwdst_addr, const ip_addr_t ipdst_addr,
ICTFBI	0:4edb816d21e1	1102	const u16_t opcode)
ICTFBI	0:4edb816d21e1	1103	{
ICTFBI	0:4edb816d21e1	1104	struct pbuf *p;
ICTFBI	0:4edb816d21e1	1105	err_t result = ERR_OK;
ICTFBI	0:4edb816d21e1	1106	struct eth_hdr *ethhdr;
ICTFBI	0:4edb816d21e1	1107	struct etharp_hdr *hdr;
ICTFBI	0:4edb816d21e1	1108	#if LWIP_AUTOIP
ICTFBI	0:4edb816d21e1	1109	const u8_t * ethdst_hwaddr;
ICTFBI	0:4edb816d21e1	1110	#endif /* LWIP_AUTOIP */
ICTFBI	0:4edb816d21e1	1111
ICTFBI	0:4edb816d21e1	1112	/* allocate a pbuf for the outgoing ARP request packet */
ICTFBI	0:4edb816d21e1	1113	p = pbuf_alloc(PBUF_RAW, SIZEOF_ETHARP_PACKET, PBUF_RAM);
ICTFBI	0:4edb816d21e1	1114	/* could allocate a pbuf for an ARP request? */
ICTFBI	0:4edb816d21e1	1115	if (p == NULL) {
ICTFBI	0:4edb816d21e1	1116	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_SERIOUS,
ICTFBI	0:4edb816d21e1	1117	("etharp_raw: could not allocate pbuf for ARP request.\n"));
ICTFBI	0:4edb816d21e1	1118	ETHARP_STATS_INC(etharp.memerr);
ICTFBI	0:4edb816d21e1	1119	return ERR_MEM;
ICTFBI	0:4edb816d21e1	1120	}
ICTFBI	0:4edb816d21e1	1121	LWIP_ASSERT("check that first pbuf can hold struct etharp_hdr",
ICTFBI	0:4edb816d21e1	1122	(p->len >= SIZEOF_ETHARP_PACKET));
ICTFBI	0:4edb816d21e1	1123
ICTFBI	0:4edb816d21e1	1124	ethhdr = (struct eth_hdr *)p->payload;
ICTFBI	0:4edb816d21e1	1125	hdr = (struct etharp_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
ICTFBI	0:4edb816d21e1	1126	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_raw: sending raw ARP packet.\n"));
ICTFBI	0:4edb816d21e1	1127	hdr->opcode = htons(opcode);
ICTFBI	0:4edb816d21e1	1128
ICTFBI	0:4edb816d21e1	1129	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
ICTFBI	0:4edb816d21e1	1130	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
ICTFBI	0:4edb816d21e1	1131	#if LWIP_AUTOIP
ICTFBI	0:4edb816d21e1	1132	/* If we are using Link-Local, all ARP packets that contain a Link-Local
ICTFBI	0:4edb816d21e1	1133	* 'sender IP address' MUST be sent using link-layer broadcast instead of
ICTFBI	0:4edb816d21e1	1134	* link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
ICTFBI	0:4edb816d21e1	1135	ethdst_hwaddr = ip_addr_islinklocal(ipsrc_addr) ? (u8_t*)(ethbroadcast.addr) : ethdst_addr->addr;
ICTFBI	0:4edb816d21e1	1136	#endif /* LWIP_AUTOIP */
ICTFBI	0:4edb816d21e1	1137	/* Write the ARP MAC-Addresses */
ICTFBI	0:4edb816d21e1	1138	ETHADDR16_COPY(&hdr->shwaddr, hwsrc_addr);
ICTFBI	0:4edb816d21e1	1139	ETHADDR16_COPY(&hdr->dhwaddr, hwdst_addr);
ICTFBI	0:4edb816d21e1	1140	/* Write the Ethernet MAC-Addresses */
ICTFBI	0:4edb816d21e1	1141	#if LWIP_AUTOIP
ICTFBI	0:4edb816d21e1	1142	ETHADDR16_COPY(&ethhdr->dest, ethdst_hwaddr);
ICTFBI	0:4edb816d21e1	1143	#else /* LWIP_AUTOIP */
ICTFBI	0:4edb816d21e1	1144	ETHADDR16_COPY(&ethhdr->dest, ethdst_addr);
ICTFBI	0:4edb816d21e1	1145	#endif /* LWIP_AUTOIP */
ICTFBI	0:4edb816d21e1	1146	ETHADDR16_COPY(&ethhdr->src, ethsrc_addr);
ICTFBI	0:4edb816d21e1	1147	/* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
ICTFBI	0:4edb816d21e1	1148	* structure packing. */
ICTFBI	0:4edb816d21e1	1149	IPADDR2_COPY(&hdr->sipaddr, ipsrc_addr);
ICTFBI	0:4edb816d21e1	1150	IPADDR2_COPY(&hdr->dipaddr, ipdst_addr);
ICTFBI	0:4edb816d21e1	1151
ICTFBI	0:4edb816d21e1	1152	hdr->hwtype = PP_HTONS(HWTYPE_ETHERNET);
ICTFBI	0:4edb816d21e1	1153	hdr->proto = PP_HTONS(ETHTYPE_IP);
ICTFBI	0:4edb816d21e1	1154	/* set hwlen and protolen */
ICTFBI	0:4edb816d21e1	1155	hdr->hwlen = ETHARP_HWADDR_LEN;
ICTFBI	0:4edb816d21e1	1156	hdr->protolen = sizeof(ip_addr_t);
ICTFBI	0:4edb816d21e1	1157
ICTFBI	0:4edb816d21e1	1158	ethhdr->type = PP_HTONS(ETHTYPE_ARP);
ICTFBI	0:4edb816d21e1	1159	/* send ARP query */
ICTFBI	0:4edb816d21e1	1160	result = netif->linkoutput(netif, p);
ICTFBI	0:4edb816d21e1	1161	ETHARP_STATS_INC(etharp.xmit);
ICTFBI	0:4edb816d21e1	1162	/* free ARP query packet */
ICTFBI	0:4edb816d21e1	1163	pbuf_free(p);
ICTFBI	0:4edb816d21e1	1164	p = NULL;
ICTFBI	0:4edb816d21e1	1165	/* could not allocate pbuf for ARP request */
ICTFBI	0:4edb816d21e1	1166
ICTFBI	0:4edb816d21e1	1167	return result;
ICTFBI	0:4edb816d21e1	1168	}
ICTFBI	0:4edb816d21e1	1169
ICTFBI	0:4edb816d21e1	1170	/**
ICTFBI	0:4edb816d21e1	1171	* Send an ARP request packet asking for ipaddr.
ICTFBI	0:4edb816d21e1	1172	*
ICTFBI	0:4edb816d21e1	1173	* @param netif the lwip network interface on which to send the request
ICTFBI	0:4edb816d21e1	1174	* @param ipaddr the IP address for which to ask
ICTFBI	0:4edb816d21e1	1175	* @return ERR_OK if the request has been sent
ICTFBI	0:4edb816d21e1	1176	* ERR_MEM if the ARP packet couldn't be allocated
ICTFBI	0:4edb816d21e1	1177	* any other err_t on failure
ICTFBI	0:4edb816d21e1	1178	*/
ICTFBI	0:4edb816d21e1	1179	err_t
ICTFBI	0:4edb816d21e1	1180	etharp_request(struct netif netif, ip_addr_t ipaddr)
ICTFBI	0:4edb816d21e1	1181	{
ICTFBI	0:4edb816d21e1	1182	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_request: sending ARP request.\n"));
ICTFBI	0:4edb816d21e1	1183	return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, &ethbroadcast,
ICTFBI	0:4edb816d21e1	1184	(struct eth_addr *)netif->hwaddr, &netif->ip_addr, &ethzero,
ICTFBI	0:4edb816d21e1	1185	ipaddr, ARP_REQUEST);
ICTFBI	0:4edb816d21e1	1186	}
ICTFBI	0:4edb816d21e1	1187	#endif /* LWIP_ARP */
ICTFBI	0:4edb816d21e1	1188
ICTFBI	0:4edb816d21e1	1189	/**
ICTFBI	0:4edb816d21e1	1190	* Process received ethernet frames. Using this function instead of directly
ICTFBI	0:4edb816d21e1	1191	* calling ip_input and passing ARP frames through etharp in ethernetif_input,
ICTFBI	0:4edb816d21e1	1192	* the ARP cache is protected from concurrent access.
ICTFBI	0:4edb816d21e1	1193	*
ICTFBI	0:4edb816d21e1	1194	* @param p the recevied packet, p->payload pointing to the ethernet header
ICTFBI	0:4edb816d21e1	1195	* @param netif the network interface on which the packet was received
ICTFBI	0:4edb816d21e1	1196	*/
ICTFBI	0:4edb816d21e1	1197	err_t
ICTFBI	0:4edb816d21e1	1198	ethernet_input(struct pbuf p, struct netif netif)
ICTFBI	0:4edb816d21e1	1199	{
ICTFBI	0:4edb816d21e1	1200	struct eth_hdr* ethhdr;
ICTFBI	0:4edb816d21e1	1201	u16_t type;
ICTFBI	0:4edb816d21e1	1202
ICTFBI	0:4edb816d21e1	1203	/* points to packet payload, which starts with an Ethernet header */
ICTFBI	0:4edb816d21e1	1204	ethhdr = (struct eth_hdr *)p->payload;
ICTFBI	0:4edb816d21e1	1205	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE,
ICTFBI	0:4edb816d21e1	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",
ICTFBI	0:4edb816d21e1	1207	(unsigned)ethhdr->dest.addr[0], (unsigned)ethhdr->dest.addr[1], (unsigned)ethhdr->dest.addr[2],
ICTFBI	0:4edb816d21e1	1208	(unsigned)ethhdr->dest.addr[3], (unsigned)ethhdr->dest.addr[4], (unsigned)ethhdr->dest.addr[5],
ICTFBI	0:4edb816d21e1	1209	(unsigned)ethhdr->src.addr[0], (unsigned)ethhdr->src.addr[1], (unsigned)ethhdr->src.addr[2],
ICTFBI	0:4edb816d21e1	1210	(unsigned)ethhdr->src.addr[3], (unsigned)ethhdr->src.addr[4], (unsigned)ethhdr->src.addr[5],
ICTFBI	0:4edb816d21e1	1211	(unsigned)htons(ethhdr->type)));
ICTFBI	0:4edb816d21e1	1212
ICTFBI	0:4edb816d21e1	1213	type = ethhdr->type;
ICTFBI	0:4edb816d21e1	1214	#if ETHARP_SUPPORT_VLAN
ICTFBI	0:4edb816d21e1	1215	if (type == PP_HTONS(ETHTYPE_VLAN)) {
ICTFBI	0:4edb816d21e1	1216	struct eth_vlan_hdr vlan = (struct eth_vlan_hdr)(((char*)ethhdr) + SIZEOF_ETH_HDR);
ICTFBI	0:4edb816d21e1	1217	#ifdef ETHARP_VLAN_CHECK /* if not, allow all VLANs */
ICTFBI	0:4edb816d21e1	1218	if (VLAN_ID(vlan) != ETHARP_VLAN_CHECK) {
ICTFBI	0:4edb816d21e1	1219	/* silently ignore this packet: not for our VLAN */
ICTFBI	0:4edb816d21e1	1220	pbuf_free(p);
ICTFBI	0:4edb816d21e1	1221	return ERR_OK;
ICTFBI	0:4edb816d21e1	1222	}
ICTFBI	0:4edb816d21e1	1223	#endif /* ETHARP_VLAN_CHECK */
ICTFBI	0:4edb816d21e1	1224	type = vlan->tpid;
ICTFBI	0:4edb816d21e1	1225	}
ICTFBI	0:4edb816d21e1	1226	#endif /* ETHARP_SUPPORT_VLAN */
ICTFBI	0:4edb816d21e1	1227
ICTFBI	0:4edb816d21e1	1228	#if LWIP_ARP_FILTER_NETIF
ICTFBI	0:4edb816d21e1	1229	netif = LWIP_ARP_FILTER_NETIF_FN(p, netif, htons(type));
ICTFBI	0:4edb816d21e1	1230	#endif /* LWIP_ARP_FILTER_NETIF*/
ICTFBI	0:4edb816d21e1	1231
ICTFBI	0:4edb816d21e1	1232	switch (type) {
ICTFBI	0:4edb816d21e1	1233	#if LWIP_ARP
ICTFBI	0:4edb816d21e1	1234	/* IP packet? */
ICTFBI	0:4edb816d21e1	1235	case PP_HTONS(ETHTYPE_IP):
ICTFBI	0:4edb816d21e1	1236	if (!(netif->flags & NETIF_FLAG_ETHARP)) {
ICTFBI	0:4edb816d21e1	1237	goto free_and_return;
ICTFBI	0:4edb816d21e1	1238	}
ICTFBI	0:4edb816d21e1	1239	#if ETHARP_TRUST_IP_MAC
ICTFBI	0:4edb816d21e1	1240	/* update ARP table */
ICTFBI	0:4edb816d21e1	1241	etharp_ip_input(netif, p);
ICTFBI	0:4edb816d21e1	1242	#endif /* ETHARP_TRUST_IP_MAC */
ICTFBI	0:4edb816d21e1	1243	/* skip Ethernet header */
ICTFBI	0:4edb816d21e1	1244	if(pbuf_header(p, -(s16_t)SIZEOF_ETH_HDR)) {
ICTFBI	0:4edb816d21e1	1245	LWIP_ASSERT("Can't move over header in packet", 0);
ICTFBI	0:4edb816d21e1	1246	goto free_and_return;
ICTFBI	0:4edb816d21e1	1247	} else {
ICTFBI	0:4edb816d21e1	1248	/* pass to IP layer */
ICTFBI	0:4edb816d21e1	1249	ip_input(p, netif);
ICTFBI	0:4edb816d21e1	1250	}
ICTFBI	0:4edb816d21e1	1251	break;
ICTFBI	0:4edb816d21e1	1252
ICTFBI	0:4edb816d21e1	1253	case PP_HTONS(ETHTYPE_ARP):
ICTFBI	0:4edb816d21e1	1254	if (!(netif->flags & NETIF_FLAG_ETHARP)) {
ICTFBI	0:4edb816d21e1	1255	goto free_and_return;
ICTFBI	0:4edb816d21e1	1256	}
ICTFBI	0:4edb816d21e1	1257	/* pass p to ARP module */
ICTFBI	0:4edb816d21e1	1258	etharp_arp_input(netif, (struct eth_addr*)(netif->hwaddr), p);
ICTFBI	0:4edb816d21e1	1259	break;
ICTFBI	0:4edb816d21e1	1260	#endif /* LWIP_ARP */
ICTFBI	0:4edb816d21e1	1261	#if PPPOE_SUPPORT
ICTFBI	0:4edb816d21e1	1262	case PP_HTONS(ETHTYPE_PPPOEDISC): /* PPP Over Ethernet Discovery Stage */
ICTFBI	0:4edb816d21e1	1263	pppoe_disc_input(netif, p);
ICTFBI	0:4edb816d21e1	1264	break;
ICTFBI	0:4edb816d21e1	1265
ICTFBI	0:4edb816d21e1	1266	case PP_HTONS(ETHTYPE_PPPOE): /* PPP Over Ethernet Session Stage */
ICTFBI	0:4edb816d21e1	1267	pppoe_data_input(netif, p);
ICTFBI	0:4edb816d21e1	1268	break;
ICTFBI	0:4edb816d21e1	1269	#endif /* PPPOE_SUPPORT */
ICTFBI	0:4edb816d21e1	1270
ICTFBI	0:4edb816d21e1	1271	default:
ICTFBI	0:4edb816d21e1	1272	ETHARP_STATS_INC(etharp.proterr);
ICTFBI	0:4edb816d21e1	1273	ETHARP_STATS_INC(etharp.drop);
ICTFBI	0:4edb816d21e1	1274	goto free_and_return;
ICTFBI	0:4edb816d21e1	1275	}
ICTFBI	0:4edb816d21e1	1276
ICTFBI	0:4edb816d21e1	1277	/* This means the pbuf is freed or consumed,
ICTFBI	0:4edb816d21e1	1278	so the caller doesn't have to free it again */
ICTFBI	0:4edb816d21e1	1279	return ERR_OK;
ICTFBI	0:4edb816d21e1	1280
ICTFBI	0:4edb816d21e1	1281	free_and_return:
ICTFBI	0:4edb816d21e1	1282	pbuf_free(p);
ICTFBI	0:4edb816d21e1	1283	return ERR_OK;
ICTFBI	0:4edb816d21e1	1284	}
ICTFBI	0:4edb816d21e1	1285	#endif /* LWIP_ARP \|\| LWIP_ETHERNET */

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Type:	Library
Created:	22 Nov 2015
Imports:	4
Forks:	0
Commits:	1
Dependents:	0
Dependencies:	1
Followers:	1

NetServices/lwip/netif/etharp.c@0:4edb816d21e1, 2015-10-16 (annotated)

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