NetServicesMinHTTPMod - Copy of NetServicesMin with the HTTP Client libra…

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Copy of NetServicesMin with the HTTP Client library. Includes modification for HTTP servers which send the HTTP status line in its own packet.

lwip/netif/etharp.c@0:18dd877d2c77, 2011-05-26 (annotated)

Committer:: andrewbonney
Date:: Thu May 26 10:02:40 2011 +0000
Revision:: 0:18dd877d2c77

Who changed what in which revision?

User	Revision	Line number	New contents of line
andrewbonney	0:18dd877d2c77	1	/**
andrewbonney	0:18dd877d2c77	2	* @file
andrewbonney	0:18dd877d2c77	3	* Address Resolution Protocol module for IP over Ethernet
andrewbonney	0:18dd877d2c77	4	*
andrewbonney	0:18dd877d2c77	5	* Functionally, ARP is divided into two parts. The first maps an IP address
andrewbonney	0:18dd877d2c77	6	* to a physical address when sending a packet, and the second part answers
andrewbonney	0:18dd877d2c77	7	* requests from other machines for our physical address.
andrewbonney	0:18dd877d2c77	8	*
andrewbonney	0:18dd877d2c77	9	* This implementation complies with RFC 826 (Ethernet ARP). It supports
andrewbonney	0:18dd877d2c77	10	* Gratuitious ARP from RFC3220 (IP Mobility Support for IPv4) section 4.6
andrewbonney	0:18dd877d2c77	11	* if an interface calls etharp_gratuitous(our_netif) upon address change.
andrewbonney	0:18dd877d2c77	12	*/
andrewbonney	0:18dd877d2c77	13
andrewbonney	0:18dd877d2c77	14	/*
andrewbonney	0:18dd877d2c77	15	* Copyright (c) 2001-2003 Swedish Institute of Computer Science.
andrewbonney	0:18dd877d2c77	16	* Copyright (c) 2003-2004 Leon Woestenberg <leon.woestenberg@axon.tv>
andrewbonney	0:18dd877d2c77	17	* Copyright (c) 2003-2004 Axon Digital Design B.V., The Netherlands.
andrewbonney	0:18dd877d2c77	18	* All rights reserved.
andrewbonney	0:18dd877d2c77	19	*
andrewbonney	0:18dd877d2c77	20	* Redistribution and use in source and binary forms, with or without modification,
andrewbonney	0:18dd877d2c77	21	* are permitted provided that the following conditions are met:
andrewbonney	0:18dd877d2c77	22	*
andrewbonney	0:18dd877d2c77	23	* 1. Redistributions of source code must retain the above copyright notice,
andrewbonney	0:18dd877d2c77	24	* this list of conditions and the following disclaimer.
andrewbonney	0:18dd877d2c77	25	* 2. Redistributions in binary form must reproduce the above copyright notice,
andrewbonney	0:18dd877d2c77	26	* this list of conditions and the following disclaimer in the documentation
andrewbonney	0:18dd877d2c77	27	* and/or other materials provided with the distribution.
andrewbonney	0:18dd877d2c77	28	* 3. The name of the author may not be used to endorse or promote products
andrewbonney	0:18dd877d2c77	29	* derived from this software without specific prior written permission.
andrewbonney	0:18dd877d2c77	30	*
andrewbonney	0:18dd877d2c77	31	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
andrewbonney	0:18dd877d2c77	32	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
andrewbonney	0:18dd877d2c77	33	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
andrewbonney	0:18dd877d2c77	34	* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
andrewbonney	0:18dd877d2c77	35	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
andrewbonney	0:18dd877d2c77	36	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
andrewbonney	0:18dd877d2c77	37	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
andrewbonney	0:18dd877d2c77	38	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
andrewbonney	0:18dd877d2c77	39	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
andrewbonney	0:18dd877d2c77	40	* OF SUCH DAMAGE.
andrewbonney	0:18dd877d2c77	41	*
andrewbonney	0:18dd877d2c77	42	* This file is part of the lwIP TCP/IP stack.
andrewbonney	0:18dd877d2c77	43	*
andrewbonney	0:18dd877d2c77	44	*/
andrewbonney	0:18dd877d2c77	45
andrewbonney	0:18dd877d2c77	46	#include "lwip/opt.h"
andrewbonney	0:18dd877d2c77	47
andrewbonney	0:18dd877d2c77	48	#if LWIP_ARP \|\| LWIP_ETHERNET
andrewbonney	0:18dd877d2c77	49
andrewbonney	0:18dd877d2c77	50	#include "lwip/ip_addr.h"
andrewbonney	0:18dd877d2c77	51	#include "lwip/def.h"
andrewbonney	0:18dd877d2c77	52	#include "lwip/ip.h"
andrewbonney	0:18dd877d2c77	53	#include "lwip/stats.h"
andrewbonney	0:18dd877d2c77	54	#include "lwip/snmp.h"
andrewbonney	0:18dd877d2c77	55	#include "lwip/dhcp.h"
andrewbonney	0:18dd877d2c77	56	#include "lwip/autoip.h"
andrewbonney	0:18dd877d2c77	57	#include "netif/etharp.h"
andrewbonney	0:18dd877d2c77	58
andrewbonney	0:18dd877d2c77	59	#if PPPOE_SUPPORT
andrewbonney	0:18dd877d2c77	60	#include "netif/ppp_oe.h"
andrewbonney	0:18dd877d2c77	61	#endif /* PPPOE_SUPPORT */
andrewbonney	0:18dd877d2c77	62
andrewbonney	0:18dd877d2c77	63	#include <string.h>
andrewbonney	0:18dd877d2c77	64
andrewbonney	0:18dd877d2c77	65	const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}};
andrewbonney	0:18dd877d2c77	66	const struct eth_addr ethzero = {{0,0,0,0,0,0}};
andrewbonney	0:18dd877d2c77	67
andrewbonney	0:18dd877d2c77	68	#if LWIP_ARP /* don't build if not configured for use in lwipopts.h */
andrewbonney	0:18dd877d2c77	69
andrewbonney	0:18dd877d2c77	70	/** the time an ARP entry stays valid after its last update,
andrewbonney	0:18dd877d2c77	71	* for ARP_TMR_INTERVAL = 5000, this is
andrewbonney	0:18dd877d2c77	72	* (240 * 5) seconds = 20 minutes.
andrewbonney	0:18dd877d2c77	73	*/
andrewbonney	0:18dd877d2c77	74	#define ARP_MAXAGE 240
andrewbonney	0:18dd877d2c77	75	/** the time an ARP entry stays pending after first request,
andrewbonney	0:18dd877d2c77	76	* for ARP_TMR_INTERVAL = 5000, this is
andrewbonney	0:18dd877d2c77	77	* (2 * 5) seconds = 10 seconds.
andrewbonney	0:18dd877d2c77	78	*
andrewbonney	0:18dd877d2c77	79	* @internal Keep this number at least 2, otherwise it might
andrewbonney	0:18dd877d2c77	80	* run out instantly if the timeout occurs directly after a request.
andrewbonney	0:18dd877d2c77	81	*/
andrewbonney	0:18dd877d2c77	82	#define ARP_MAXPENDING 2
andrewbonney	0:18dd877d2c77	83
andrewbonney	0:18dd877d2c77	84	#define HWTYPE_ETHERNET 1
andrewbonney	0:18dd877d2c77	85
andrewbonney	0:18dd877d2c77	86	enum etharp_state {
andrewbonney	0:18dd877d2c77	87	ETHARP_STATE_EMPTY = 0,
andrewbonney	0:18dd877d2c77	88	ETHARP_STATE_PENDING,
andrewbonney	0:18dd877d2c77	89	ETHARP_STATE_STABLE
andrewbonney	0:18dd877d2c77	90	};
andrewbonney	0:18dd877d2c77	91
andrewbonney	0:18dd877d2c77	92	struct etharp_entry {
andrewbonney	0:18dd877d2c77	93	#if ARP_QUEUEING
andrewbonney	0:18dd877d2c77	94	/** Pointer to queue of pending outgoing packets on this ARP entry. */
andrewbonney	0:18dd877d2c77	95	struct etharp_q_entry *q;
andrewbonney	0:18dd877d2c77	96	#endif /* ARP_QUEUEING */
andrewbonney	0:18dd877d2c77	97	ip_addr_t ipaddr;
andrewbonney	0:18dd877d2c77	98	struct eth_addr ethaddr;
andrewbonney	0:18dd877d2c77	99	#if LWIP_SNMP
andrewbonney	0:18dd877d2c77	100	struct netif *netif;
andrewbonney	0:18dd877d2c77	101	#endif /* LWIP_SNMP */
andrewbonney	0:18dd877d2c77	102	u8_t state;
andrewbonney	0:18dd877d2c77	103	u8_t ctime;
andrewbonney	0:18dd877d2c77	104	#if ETHARP_SUPPORT_STATIC_ENTRIES
andrewbonney	0:18dd877d2c77	105	u8_t static_entry;
andrewbonney	0:18dd877d2c77	106	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
andrewbonney	0:18dd877d2c77	107	};
andrewbonney	0:18dd877d2c77	108
andrewbonney	0:18dd877d2c77	109	static struct etharp_entry arp_table[ARP_TABLE_SIZE];
andrewbonney	0:18dd877d2c77	110
andrewbonney	0:18dd877d2c77	111	#if !LWIP_NETIF_HWADDRHINT
andrewbonney	0:18dd877d2c77	112	static u8_t etharp_cached_entry;
andrewbonney	0:18dd877d2c77	113	#endif /* !LWIP_NETIF_HWADDRHINT */
andrewbonney	0:18dd877d2c77	114
andrewbonney	0:18dd877d2c77	115	/** Try hard to create a new entry - we want the IP address to appear in
andrewbonney	0:18dd877d2c77	116	the cache (even if this means removing an active entry or so). */
andrewbonney	0:18dd877d2c77	117	#define ETHARP_FLAG_TRY_HARD 1
andrewbonney	0:18dd877d2c77	118	#define ETHARP_FLAG_FIND_ONLY 2
andrewbonney	0:18dd877d2c77	119	#define ETHARP_FLAG_STATIC_ENTRY 4
andrewbonney	0:18dd877d2c77	120
andrewbonney	0:18dd877d2c77	121	#if LWIP_NETIF_HWADDRHINT
andrewbonney	0:18dd877d2c77	122	#define ETHARP_SET_HINT(netif, hint) if (((netif) != NULL) && ((netif)->addr_hint != NULL)) \
andrewbonney	0:18dd877d2c77	123	*((netif)->addr_hint) = (hint);
andrewbonney	0:18dd877d2c77	124	#else /* LWIP_NETIF_HWADDRHINT */
andrewbonney	0:18dd877d2c77	125	#define ETHARP_SET_HINT(netif, hint) (etharp_cached_entry = (hint))
andrewbonney	0:18dd877d2c77	126	#endif /* LWIP_NETIF_HWADDRHINT */
andrewbonney	0:18dd877d2c77	127
andrewbonney	0:18dd877d2c77	128	static err_t update_arp_entry(struct netif netif, ip_addr_t ipaddr, struct eth_addr *ethaddr, u8_t flags);
andrewbonney	0:18dd877d2c77	129
andrewbonney	0:18dd877d2c77	130
andrewbonney	0:18dd877d2c77	131	/* Some checks, instead of etharp_init(): */
andrewbonney	0:18dd877d2c77	132	#if (LWIP_ARP && (ARP_TABLE_SIZE > 0x7f))
andrewbonney	0:18dd877d2c77	133	#error "ARP_TABLE_SIZE must fit in an s8_t, you have to reduce it in your lwipopts.h"
andrewbonney	0:18dd877d2c77	134	#endif
andrewbonney	0:18dd877d2c77	135
andrewbonney	0:18dd877d2c77	136
andrewbonney	0:18dd877d2c77	137	#if ARP_QUEUEING
andrewbonney	0:18dd877d2c77	138	/**
andrewbonney	0:18dd877d2c77	139	* Free a complete queue of etharp entries
andrewbonney	0:18dd877d2c77	140	*
andrewbonney	0:18dd877d2c77	141	* @param q a qeueue of etharp_q_entry's to free
andrewbonney	0:18dd877d2c77	142	*/
andrewbonney	0:18dd877d2c77	143	static void
andrewbonney	0:18dd877d2c77	144	free_etharp_q(struct etharp_q_entry *q)
andrewbonney	0:18dd877d2c77	145	{
andrewbonney	0:18dd877d2c77	146	struct etharp_q_entry *r;
andrewbonney	0:18dd877d2c77	147	LWIP_ASSERT("q != NULL", q != NULL);
andrewbonney	0:18dd877d2c77	148	LWIP_ASSERT("q->p != NULL", q->p != NULL);
andrewbonney	0:18dd877d2c77	149	while (q) {
andrewbonney	0:18dd877d2c77	150	r = q;
andrewbonney	0:18dd877d2c77	151	q = q->next;
andrewbonney	0:18dd877d2c77	152	LWIP_ASSERT("r->p != NULL", (r->p != NULL));
andrewbonney	0:18dd877d2c77	153	pbuf_free(r->p);
andrewbonney	0:18dd877d2c77	154	memp_free(MEMP_ARP_QUEUE, r);
andrewbonney	0:18dd877d2c77	155	}
andrewbonney	0:18dd877d2c77	156	}
andrewbonney	0:18dd877d2c77	157	#endif /* ARP_QUEUEING */
andrewbonney	0:18dd877d2c77	158
andrewbonney	0:18dd877d2c77	159	/** Clean up ARP table entries */
andrewbonney	0:18dd877d2c77	160	static void
andrewbonney	0:18dd877d2c77	161	free_entry(int i)
andrewbonney	0:18dd877d2c77	162	{
andrewbonney	0:18dd877d2c77	163	/* remove from SNMP ARP index tree */
andrewbonney	0:18dd877d2c77	164	snmp_delete_arpidx_tree(arp_table[i].netif, &arp_table[i].ipaddr);
andrewbonney	0:18dd877d2c77	165	#if ARP_QUEUEING
andrewbonney	0:18dd877d2c77	166	/* and empty packet queue */
andrewbonney	0:18dd877d2c77	167	if (arp_table[i].q != NULL) {
andrewbonney	0:18dd877d2c77	168	/* remove all queued packets */
andrewbonney	0:18dd877d2c77	169	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: freeing entry %"U16_F", packet queue %p.\n", (u16_t)i, (void *)(arp_table[i].q)));
andrewbonney	0:18dd877d2c77	170	free_etharp_q(arp_table[i].q);
andrewbonney	0:18dd877d2c77	171	arp_table[i].q = NULL;
andrewbonney	0:18dd877d2c77	172	}
andrewbonney	0:18dd877d2c77	173	#endif /* ARP_QUEUEING */
andrewbonney	0:18dd877d2c77	174	/* recycle entry for re-use */
andrewbonney	0:18dd877d2c77	175	arp_table[i].state = ETHARP_STATE_EMPTY;
andrewbonney	0:18dd877d2c77	176	#if ETHARP_SUPPORT_STATIC_ENTRIES
andrewbonney	0:18dd877d2c77	177	arp_table[i].static_entry = 0;
andrewbonney	0:18dd877d2c77	178	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
andrewbonney	0:18dd877d2c77	179	#ifdef LWIP_DEBUG
andrewbonney	0:18dd877d2c77	180	/* for debugging, clean out the complete entry */
andrewbonney	0:18dd877d2c77	181	arp_table[i].ctime = 0;
andrewbonney	0:18dd877d2c77	182	#if LWIP_SNMP
andrewbonney	0:18dd877d2c77	183	arp_table[i].netif = NULL;
andrewbonney	0:18dd877d2c77	184	#endif /* LWIP_SNMP */
andrewbonney	0:18dd877d2c77	185	ip_addr_set_zero(&arp_table[i].ipaddr);
andrewbonney	0:18dd877d2c77	186	arp_table[i].ethaddr = ethzero;
andrewbonney	0:18dd877d2c77	187	#endif /* LWIP_DEBUG */
andrewbonney	0:18dd877d2c77	188	}
andrewbonney	0:18dd877d2c77	189
andrewbonney	0:18dd877d2c77	190	/**
andrewbonney	0:18dd877d2c77	191	* Clears expired entries in the ARP table.
andrewbonney	0:18dd877d2c77	192	*
andrewbonney	0:18dd877d2c77	193	* This function should be called every ETHARP_TMR_INTERVAL milliseconds (5 seconds),
andrewbonney	0:18dd877d2c77	194	* in order to expire entries in the ARP table.
andrewbonney	0:18dd877d2c77	195	*/
andrewbonney	0:18dd877d2c77	196	void
andrewbonney	0:18dd877d2c77	197	etharp_tmr(void)
andrewbonney	0:18dd877d2c77	198	{
andrewbonney	0:18dd877d2c77	199	u8_t i;
andrewbonney	0:18dd877d2c77	200
andrewbonney	0:18dd877d2c77	201	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer\n"));
andrewbonney	0:18dd877d2c77	202	/* remove expired entries from the ARP table */
andrewbonney	0:18dd877d2c77	203	for (i = 0; i < ARP_TABLE_SIZE; ++i) {
andrewbonney	0:18dd877d2c77	204	u8_t state = arp_table[i].state;
andrewbonney	0:18dd877d2c77	205	if (state != ETHARP_STATE_EMPTY
andrewbonney	0:18dd877d2c77	206	#if ETHARP_SUPPORT_STATIC_ENTRIES
andrewbonney	0:18dd877d2c77	207	&& (arp_table[i].static_entry == 0)
andrewbonney	0:18dd877d2c77	208	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
andrewbonney	0:18dd877d2c77	209	) {
andrewbonney	0:18dd877d2c77	210	arp_table[i].ctime++;
andrewbonney	0:18dd877d2c77	211	if ((arp_table[i].ctime >= ARP_MAXAGE) \|\|
andrewbonney	0:18dd877d2c77	212	((arp_table[i].state == ETHARP_STATE_PENDING) &&
andrewbonney	0:18dd877d2c77	213	(arp_table[i].ctime >= ARP_MAXPENDING))) {
andrewbonney	0:18dd877d2c77	214	/* pending or stable entry has become old! */
andrewbonney	0:18dd877d2c77	215	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: expired %s entry %"U16_F".\n",
andrewbonney	0:18dd877d2c77	216	arp_table[i].state == ETHARP_STATE_STABLE ? "stable" : "pending", (u16_t)i));
andrewbonney	0:18dd877d2c77	217	/* clean up entries that have just been expired */
andrewbonney	0:18dd877d2c77	218	free_entry(i);
andrewbonney	0:18dd877d2c77	219	}
andrewbonney	0:18dd877d2c77	220	#if ARP_QUEUEING
andrewbonney	0:18dd877d2c77	221	/* still pending entry? (not expired) */
andrewbonney	0:18dd877d2c77	222	if (arp_table[i].state == ETHARP_STATE_PENDING) {
andrewbonney	0:18dd877d2c77	223	/* resend an ARP query here? */
andrewbonney	0:18dd877d2c77	224	}
andrewbonney	0:18dd877d2c77	225	#endif /* ARP_QUEUEING */
andrewbonney	0:18dd877d2c77	226	}
andrewbonney	0:18dd877d2c77	227	}
andrewbonney	0:18dd877d2c77	228	}
andrewbonney	0:18dd877d2c77	229
andrewbonney	0:18dd877d2c77	230	/**
andrewbonney	0:18dd877d2c77	231	* Search the ARP table for a matching or new entry.
andrewbonney	0:18dd877d2c77	232	*
andrewbonney	0:18dd877d2c77	233	* If an IP address is given, return a pending or stable ARP entry that matches
andrewbonney	0:18dd877d2c77	234	* the address. If no match is found, create a new entry with this address set,
andrewbonney	0:18dd877d2c77	235	* but in state ETHARP_EMPTY. The caller must check and possibly change the
andrewbonney	0:18dd877d2c77	236	* state of the returned entry.
andrewbonney	0:18dd877d2c77	237	*
andrewbonney	0:18dd877d2c77	238	* If ipaddr is NULL, return a initialized new entry in state ETHARP_EMPTY.
andrewbonney	0:18dd877d2c77	239	*
andrewbonney	0:18dd877d2c77	240	* In all cases, attempt to create new entries from an empty entry. If no
andrewbonney	0:18dd877d2c77	241	* empty entries are available and ETHARP_FLAG_TRY_HARD flag is set, recycle
andrewbonney	0:18dd877d2c77	242	* old entries. Heuristic choose the least important entry for recycling.
andrewbonney	0:18dd877d2c77	243	*
andrewbonney	0:18dd877d2c77	244	* @param ipaddr IP address to find in ARP cache, or to add if not found.
andrewbonney	0:18dd877d2c77	245	* @param flags @see definition of ETHARP_FLAG_*
andrewbonney	0:18dd877d2c77	246	* @param netif netif related to this address (used for NETIF_HWADDRHINT)
andrewbonney	0:18dd877d2c77	247	*
andrewbonney	0:18dd877d2c77	248	* @return The ARP entry index that matched or is created, ERR_MEM if no
andrewbonney	0:18dd877d2c77	249	* entry is found or could be recycled.
andrewbonney	0:18dd877d2c77	250	*/
andrewbonney	0:18dd877d2c77	251	static s8_t
andrewbonney	0:18dd877d2c77	252	find_entry(ip_addr_t *ipaddr, u8_t flags)
andrewbonney	0:18dd877d2c77	253	{
andrewbonney	0:18dd877d2c77	254	s8_t old_pending = ARP_TABLE_SIZE, old_stable = ARP_TABLE_SIZE;
andrewbonney	0:18dd877d2c77	255	s8_t empty = ARP_TABLE_SIZE;
andrewbonney	0:18dd877d2c77	256	u8_t i = 0, age_pending = 0, age_stable = 0;
andrewbonney	0:18dd877d2c77	257	#if ARP_QUEUEING
andrewbonney	0:18dd877d2c77	258	/* oldest entry with packets on queue */
andrewbonney	0:18dd877d2c77	259	s8_t old_queue = ARP_TABLE_SIZE;
andrewbonney	0:18dd877d2c77	260	/* its age */
andrewbonney	0:18dd877d2c77	261	u8_t age_queue = 0;
andrewbonney	0:18dd877d2c77	262	#endif /* ARP_QUEUEING */
andrewbonney	0:18dd877d2c77	263
andrewbonney	0:18dd877d2c77	264	/**
andrewbonney	0:18dd877d2c77	265	* a) do a search through the cache, remember candidates
andrewbonney	0:18dd877d2c77	266	* b) select candidate entry
andrewbonney	0:18dd877d2c77	267	* c) create new entry
andrewbonney	0:18dd877d2c77	268	*/
andrewbonney	0:18dd877d2c77	269
andrewbonney	0:18dd877d2c77	270	/* a) in a single search sweep, do all of this
andrewbonney	0:18dd877d2c77	271	* 1) remember the first empty entry (if any)
andrewbonney	0:18dd877d2c77	272	* 2) remember the oldest stable entry (if any)
andrewbonney	0:18dd877d2c77	273	* 3) remember the oldest pending entry without queued packets (if any)
andrewbonney	0:18dd877d2c77	274	* 4) remember the oldest pending entry with queued packets (if any)
andrewbonney	0:18dd877d2c77	275	* 5) search for a matching IP entry, either pending or stable
andrewbonney	0:18dd877d2c77	276	* until 5 matches, or all entries are searched for.
andrewbonney	0:18dd877d2c77	277	*/
andrewbonney	0:18dd877d2c77	278
andrewbonney	0:18dd877d2c77	279	for (i = 0; i < ARP_TABLE_SIZE; ++i) {
andrewbonney	0:18dd877d2c77	280	u8_t state = arp_table[i].state;
andrewbonney	0:18dd877d2c77	281	/* no empty entry found yet and now we do find one? */
andrewbonney	0:18dd877d2c77	282	if ((empty == ARP_TABLE_SIZE) && (state == ETHARP_STATE_EMPTY)) {
andrewbonney	0:18dd877d2c77	283	LWIP_DEBUGF(ETHARP_DEBUG, ("find_entry: found empty entry %"U16_F"\n", (u16_t)i));
andrewbonney	0:18dd877d2c77	284	/* remember first empty entry */
andrewbonney	0:18dd877d2c77	285	empty = i;
andrewbonney	0:18dd877d2c77	286	} else if (state != ETHARP_STATE_EMPTY) {
andrewbonney	0:18dd877d2c77	287	LWIP_ASSERT("state == ETHARP_STATE_PENDING \|\| state == ETHARP_STATE_STABLE",
andrewbonney	0:18dd877d2c77	288	state == ETHARP_STATE_PENDING \|\| state == ETHARP_STATE_STABLE);
andrewbonney	0:18dd877d2c77	289	/* if given, does IP address match IP address in ARP entry? */
andrewbonney	0:18dd877d2c77	290	if (ipaddr && ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
andrewbonney	0:18dd877d2c77	291	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: found matching entry %"U16_F"\n", (u16_t)i));
andrewbonney	0:18dd877d2c77	292	/* found exact IP address match, simply bail out */
andrewbonney	0:18dd877d2c77	293	return i;
andrewbonney	0:18dd877d2c77	294	}
andrewbonney	0:18dd877d2c77	295	/* pending entry? */
andrewbonney	0:18dd877d2c77	296	if (state == ETHARP_STATE_PENDING) {
andrewbonney	0:18dd877d2c77	297	/* pending with queued packets? */
andrewbonney	0:18dd877d2c77	298	#if ARP_QUEUEING
andrewbonney	0:18dd877d2c77	299	if (arp_table[i].q != NULL) {
andrewbonney	0:18dd877d2c77	300	if (arp_table[i].ctime >= age_queue) {
andrewbonney	0:18dd877d2c77	301	old_queue = i;
andrewbonney	0:18dd877d2c77	302	age_queue = arp_table[i].ctime;
andrewbonney	0:18dd877d2c77	303	}
andrewbonney	0:18dd877d2c77	304	} else
andrewbonney	0:18dd877d2c77	305	#endif /* ARP_QUEUEING */
andrewbonney	0:18dd877d2c77	306	/* pending without queued packets? */
andrewbonney	0:18dd877d2c77	307	{
andrewbonney	0:18dd877d2c77	308	if (arp_table[i].ctime >= age_pending) {
andrewbonney	0:18dd877d2c77	309	old_pending = i;
andrewbonney	0:18dd877d2c77	310	age_pending = arp_table[i].ctime;
andrewbonney	0:18dd877d2c77	311	}
andrewbonney	0:18dd877d2c77	312	}
andrewbonney	0:18dd877d2c77	313	/* stable entry? */
andrewbonney	0:18dd877d2c77	314	} else if (state == ETHARP_STATE_STABLE) {
andrewbonney	0:18dd877d2c77	315	#if ETHARP_SUPPORT_STATIC_ENTRIES
andrewbonney	0:18dd877d2c77	316	/* don't record old_stable for static entries since they never expire */
andrewbonney	0:18dd877d2c77	317	if (arp_table[i].static_entry == 0)
andrewbonney	0:18dd877d2c77	318	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
andrewbonney	0:18dd877d2c77	319	{
andrewbonney	0:18dd877d2c77	320	/* remember entry with oldest stable entry in oldest, its age in maxtime */
andrewbonney	0:18dd877d2c77	321	if (arp_table[i].ctime >= age_stable) {
andrewbonney	0:18dd877d2c77	322	old_stable = i;
andrewbonney	0:18dd877d2c77	323	age_stable = arp_table[i].ctime;
andrewbonney	0:18dd877d2c77	324	}
andrewbonney	0:18dd877d2c77	325	}
andrewbonney	0:18dd877d2c77	326	}
andrewbonney	0:18dd877d2c77	327	}
andrewbonney	0:18dd877d2c77	328	}
andrewbonney	0:18dd877d2c77	329	/* { we have no match } => try to create a new entry */
andrewbonney	0:18dd877d2c77	330
andrewbonney	0:18dd877d2c77	331	/* don't create new entry, only search? */
andrewbonney	0:18dd877d2c77	332	if (((flags & ETHARP_FLAG_FIND_ONLY) != 0) \|\|
andrewbonney	0:18dd877d2c77	333	/* or no empty entry found and not allowed to recycle? */
andrewbonney	0:18dd877d2c77	334	((empty == ARP_TABLE_SIZE) && ((flags & ETHARP_FLAG_TRY_HARD) == 0))) {
andrewbonney	0:18dd877d2c77	335	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: no empty entry found and not allowed to recycle\n"));
andrewbonney	0:18dd877d2c77	336	return (s8_t)ERR_MEM;
andrewbonney	0:18dd877d2c77	337	}
andrewbonney	0:18dd877d2c77	338
andrewbonney	0:18dd877d2c77	339	/* b) choose the least destructive entry to recycle:
andrewbonney	0:18dd877d2c77	340	* 1) empty entry
andrewbonney	0:18dd877d2c77	341	* 2) oldest stable entry
andrewbonney	0:18dd877d2c77	342	* 3) oldest pending entry without queued packets
andrewbonney	0:18dd877d2c77	343	* 4) oldest pending entry with queued packets
andrewbonney	0:18dd877d2c77	344	*
andrewbonney	0:18dd877d2c77	345	* { ETHARP_FLAG_TRY_HARD is set at this point }
andrewbonney	0:18dd877d2c77	346	*/
andrewbonney	0:18dd877d2c77	347
andrewbonney	0:18dd877d2c77	348	/* 1) empty entry available? */
andrewbonney	0:18dd877d2c77	349	if (empty < ARP_TABLE_SIZE) {
andrewbonney	0:18dd877d2c77	350	i = empty;
andrewbonney	0:18dd877d2c77	351	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting empty entry %"U16_F"\n", (u16_t)i));
andrewbonney	0:18dd877d2c77	352	} else {
andrewbonney	0:18dd877d2c77	353	/* 2) found recyclable stable entry? */
andrewbonney	0:18dd877d2c77	354	if (old_stable < ARP_TABLE_SIZE) {
andrewbonney	0:18dd877d2c77	355	/* recycle oldest stable*/
andrewbonney	0:18dd877d2c77	356	i = old_stable;
andrewbonney	0:18dd877d2c77	357	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest stable entry %"U16_F"\n", (u16_t)i));
andrewbonney	0:18dd877d2c77	358	#if ARP_QUEUEING
andrewbonney	0:18dd877d2c77	359	/* no queued packets should exist on stable entries */
andrewbonney	0:18dd877d2c77	360	LWIP_ASSERT("arp_table[i].q == NULL", arp_table[i].q == NULL);
andrewbonney	0:18dd877d2c77	361	#endif /* ARP_QUEUEING */
andrewbonney	0:18dd877d2c77	362	/* 3) found recyclable pending entry without queued packets? */
andrewbonney	0:18dd877d2c77	363	} else if (old_pending < ARP_TABLE_SIZE) {
andrewbonney	0:18dd877d2c77	364	/* recycle oldest pending */
andrewbonney	0:18dd877d2c77	365	i = old_pending;
andrewbonney	0:18dd877d2c77	366	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest pending entry %"U16_F" (without queue)\n", (u16_t)i));
andrewbonney	0:18dd877d2c77	367	#if ARP_QUEUEING
andrewbonney	0:18dd877d2c77	368	/* 4) found recyclable pending entry with queued packets? */
andrewbonney	0:18dd877d2c77	369	} else if (old_queue < ARP_TABLE_SIZE) {
andrewbonney	0:18dd877d2c77	370	/* recycle oldest pending (queued packets are free in free_entry) */
andrewbonney	0:18dd877d2c77	371	i = old_queue;
andrewbonney	0:18dd877d2c77	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)));
andrewbonney	0:18dd877d2c77	373	#endif /* ARP_QUEUEING */
andrewbonney	0:18dd877d2c77	374	/* no empty or recyclable entries found */
andrewbonney	0:18dd877d2c77	375	} else {
andrewbonney	0:18dd877d2c77	376	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: no empty or recyclable entries found\n"));
andrewbonney	0:18dd877d2c77	377	return (s8_t)ERR_MEM;
andrewbonney	0:18dd877d2c77	378	}
andrewbonney	0:18dd877d2c77	379
andrewbonney	0:18dd877d2c77	380	/* { empty or recyclable entry found } */
andrewbonney	0:18dd877d2c77	381	LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
andrewbonney	0:18dd877d2c77	382	free_entry(i);
andrewbonney	0:18dd877d2c77	383	}
andrewbonney	0:18dd877d2c77	384
andrewbonney	0:18dd877d2c77	385	LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
andrewbonney	0:18dd877d2c77	386	LWIP_ASSERT("arp_table[i].state == ETHARP_STATE_EMPTY",
andrewbonney	0:18dd877d2c77	387	arp_table[i].state == ETHARP_STATE_EMPTY);
andrewbonney	0:18dd877d2c77	388
andrewbonney	0:18dd877d2c77	389	/* IP address given? */
andrewbonney	0:18dd877d2c77	390	if (ipaddr != NULL) {
andrewbonney	0:18dd877d2c77	391	/* set IP address */
andrewbonney	0:18dd877d2c77	392	ip_addr_copy(arp_table[i].ipaddr, *ipaddr);
andrewbonney	0:18dd877d2c77	393	}
andrewbonney	0:18dd877d2c77	394	arp_table[i].ctime = 0;
andrewbonney	0:18dd877d2c77	395	#if ETHARP_SUPPORT_STATIC_ENTRIES
andrewbonney	0:18dd877d2c77	396	arp_table[i].static_entry = 0;
andrewbonney	0:18dd877d2c77	397	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
andrewbonney	0:18dd877d2c77	398	return (err_t)i;
andrewbonney	0:18dd877d2c77	399	}
andrewbonney	0:18dd877d2c77	400
andrewbonney	0:18dd877d2c77	401	/**
andrewbonney	0:18dd877d2c77	402	* Send an IP packet on the network using netif->linkoutput
andrewbonney	0:18dd877d2c77	403	* The ethernet header is filled in before sending.
andrewbonney	0:18dd877d2c77	404	*
andrewbonney	0:18dd877d2c77	405	* @params netif the lwIP network interface on which to send the packet
andrewbonney	0:18dd877d2c77	406	* @params p the packet to send, p->payload pointing to the (uninitialized) ethernet header
andrewbonney	0:18dd877d2c77	407	* @params src the source MAC address to be copied into the ethernet header
andrewbonney	0:18dd877d2c77	408	* @params dst the destination MAC address to be copied into the ethernet header
andrewbonney	0:18dd877d2c77	409	* @return ERR_OK if the packet was sent, any other err_t on failure
andrewbonney	0:18dd877d2c77	410	*/
andrewbonney	0:18dd877d2c77	411	static err_t
andrewbonney	0:18dd877d2c77	412	etharp_send_ip(struct netif netif, struct pbuf p, struct eth_addr src, struct eth_addr dst)
andrewbonney	0:18dd877d2c77	413	{
andrewbonney	0:18dd877d2c77	414	struct eth_hdr ethhdr = (struct eth_hdr )p->payload;
andrewbonney	0:18dd877d2c77	415
andrewbonney	0:18dd877d2c77	416	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
andrewbonney	0:18dd877d2c77	417	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
andrewbonney	0:18dd877d2c77	418	ETHADDR32_COPY(&ethhdr->dest, dst);
andrewbonney	0:18dd877d2c77	419	ETHADDR16_COPY(&ethhdr->src, src);
andrewbonney	0:18dd877d2c77	420	ethhdr->type = PP_HTONS(ETHTYPE_IP);
andrewbonney	0:18dd877d2c77	421	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_send_ip: sending packet %p\n", (void *)p));
andrewbonney	0:18dd877d2c77	422	/* send the packet */
andrewbonney	0:18dd877d2c77	423	return netif->linkoutput(netif, p);
andrewbonney	0:18dd877d2c77	424	}
andrewbonney	0:18dd877d2c77	425
andrewbonney	0:18dd877d2c77	426	/**
andrewbonney	0:18dd877d2c77	427	* Update (or insert) a IP/MAC address pair in the ARP cache.
andrewbonney	0:18dd877d2c77	428	*
andrewbonney	0:18dd877d2c77	429	* If a pending entry is resolved, any queued packets will be sent
andrewbonney	0:18dd877d2c77	430	* at this point.
andrewbonney	0:18dd877d2c77	431	*
andrewbonney	0:18dd877d2c77	432	* @param netif netif related to this entry (used for NETIF_ADDRHINT)
andrewbonney	0:18dd877d2c77	433	* @param ipaddr IP address of the inserted ARP entry.
andrewbonney	0:18dd877d2c77	434	* @param ethaddr Ethernet address of the inserted ARP entry.
andrewbonney	0:18dd877d2c77	435	* @param flags @see definition of ETHARP_FLAG_*
andrewbonney	0:18dd877d2c77	436	*
andrewbonney	0:18dd877d2c77	437	* @return
andrewbonney	0:18dd877d2c77	438	* - ERR_OK Succesfully updated ARP cache.
andrewbonney	0:18dd877d2c77	439	* - ERR_MEM If we could not add a new ARP entry when ETHARP_FLAG_TRY_HARD was set.
andrewbonney	0:18dd877d2c77	440	* - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
andrewbonney	0:18dd877d2c77	441	*
andrewbonney	0:18dd877d2c77	442	* @see pbuf_free()
andrewbonney	0:18dd877d2c77	443	*/
andrewbonney	0:18dd877d2c77	444	static err_t
andrewbonney	0:18dd877d2c77	445	update_arp_entry(struct netif netif, ip_addr_t ipaddr, struct eth_addr *ethaddr, u8_t flags)
andrewbonney	0:18dd877d2c77	446	{
andrewbonney	0:18dd877d2c77	447	s8_t i;
andrewbonney	0:18dd877d2c77	448	LWIP_ASSERT("netif->hwaddr_len == ETHARP_HWADDR_LEN", netif->hwaddr_len == ETHARP_HWADDR_LEN);
andrewbonney	0:18dd877d2c77	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",
andrewbonney	0:18dd877d2c77	450	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
andrewbonney	0:18dd877d2c77	451	ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
andrewbonney	0:18dd877d2c77	452	ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
andrewbonney	0:18dd877d2c77	453	/* non-unicast address? */
andrewbonney	0:18dd877d2c77	454	if (ip_addr_isany(ipaddr) \|\|
andrewbonney	0:18dd877d2c77	455	ip_addr_isbroadcast(ipaddr, netif) \|\|
andrewbonney	0:18dd877d2c77	456	ip_addr_ismulticast(ipaddr)) {
andrewbonney	0:18dd877d2c77	457	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: will not add non-unicast IP address to ARP cache\n"));
andrewbonney	0:18dd877d2c77	458	return ERR_ARG;
andrewbonney	0:18dd877d2c77	459	}
andrewbonney	0:18dd877d2c77	460	/* find or create ARP entry */
andrewbonney	0:18dd877d2c77	461	i = find_entry(ipaddr, flags);
andrewbonney	0:18dd877d2c77	462	/* bail out if no entry could be found */
andrewbonney	0:18dd877d2c77	463	if (i < 0) {
andrewbonney	0:18dd877d2c77	464	return (err_t)i;
andrewbonney	0:18dd877d2c77	465	}
andrewbonney	0:18dd877d2c77	466
andrewbonney	0:18dd877d2c77	467	#if ETHARP_SUPPORT_STATIC_ENTRIES
andrewbonney	0:18dd877d2c77	468	if (flags & ETHARP_FLAG_STATIC_ENTRY) {
andrewbonney	0:18dd877d2c77	469	/* record static type */
andrewbonney	0:18dd877d2c77	470	arp_table[i].static_entry = 1;
andrewbonney	0:18dd877d2c77	471	}
andrewbonney	0:18dd877d2c77	472	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
andrewbonney	0:18dd877d2c77	473
andrewbonney	0:18dd877d2c77	474	/* mark it stable */
andrewbonney	0:18dd877d2c77	475	arp_table[i].state = ETHARP_STATE_STABLE;
andrewbonney	0:18dd877d2c77	476
andrewbonney	0:18dd877d2c77	477	#if LWIP_SNMP
andrewbonney	0:18dd877d2c77	478	/* record network interface */
andrewbonney	0:18dd877d2c77	479	arp_table[i].netif = netif;
andrewbonney	0:18dd877d2c77	480	#endif /* LWIP_SNMP */
andrewbonney	0:18dd877d2c77	481	/* insert in SNMP ARP index tree */
andrewbonney	0:18dd877d2c77	482	snmp_insert_arpidx_tree(netif, &arp_table[i].ipaddr);
andrewbonney	0:18dd877d2c77	483
andrewbonney	0:18dd877d2c77	484	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: updating stable entry %"S16_F"\n", (s16_t)i));
andrewbonney	0:18dd877d2c77	485	/* update address */
andrewbonney	0:18dd877d2c77	486	ETHADDR32_COPY(&arp_table[i].ethaddr, ethaddr);
andrewbonney	0:18dd877d2c77	487	/* reset time stamp */
andrewbonney	0:18dd877d2c77	488	arp_table[i].ctime = 0;
andrewbonney	0:18dd877d2c77	489	#if ARP_QUEUEING
andrewbonney	0:18dd877d2c77	490	/* this is where we will send out queued packets! */
andrewbonney	0:18dd877d2c77	491	while (arp_table[i].q != NULL) {
andrewbonney	0:18dd877d2c77	492	struct pbuf *p;
andrewbonney	0:18dd877d2c77	493	/* remember remainder of queue */
andrewbonney	0:18dd877d2c77	494	struct etharp_q_entry *q = arp_table[i].q;
andrewbonney	0:18dd877d2c77	495	/* pop first item off the queue */
andrewbonney	0:18dd877d2c77	496	arp_table[i].q = q->next;
andrewbonney	0:18dd877d2c77	497	/* get the packet pointer */
andrewbonney	0:18dd877d2c77	498	p = q->p;
andrewbonney	0:18dd877d2c77	499	/* now queue entry can be freed */
andrewbonney	0:18dd877d2c77	500	memp_free(MEMP_ARP_QUEUE, q);
andrewbonney	0:18dd877d2c77	501	/* send the queued IP packet */
andrewbonney	0:18dd877d2c77	502	etharp_send_ip(netif, p, (struct eth_addr*)(netif->hwaddr), ethaddr);
andrewbonney	0:18dd877d2c77	503	/* free the queued IP packet */
andrewbonney	0:18dd877d2c77	504	pbuf_free(p);
andrewbonney	0:18dd877d2c77	505	}
andrewbonney	0:18dd877d2c77	506	#endif /* ARP_QUEUEING */
andrewbonney	0:18dd877d2c77	507	return ERR_OK;
andrewbonney	0:18dd877d2c77	508	}
andrewbonney	0:18dd877d2c77	509
andrewbonney	0:18dd877d2c77	510	#if ETHARP_SUPPORT_STATIC_ENTRIES
andrewbonney	0:18dd877d2c77	511	/** Add a new static entry to the ARP table. If an entry exists for the
andrewbonney	0:18dd877d2c77	512	* specified IP address, this entry is overwritten.
andrewbonney	0:18dd877d2c77	513	* If packets are queued for the specified IP address, they are sent out.
andrewbonney	0:18dd877d2c77	514	*
andrewbonney	0:18dd877d2c77	515	* @param ipaddr IP address for the new static entry
andrewbonney	0:18dd877d2c77	516	* @param ethaddr ethernet address for the new static entry
andrewbonney	0:18dd877d2c77	517	* @return @see return values of etharp_add_static_entry
andrewbonney	0:18dd877d2c77	518	*/
andrewbonney	0:18dd877d2c77	519	err_t
andrewbonney	0:18dd877d2c77	520	etharp_add_static_entry(ip_addr_t ipaddr, struct eth_addr ethaddr)
andrewbonney	0:18dd877d2c77	521	{
andrewbonney	0:18dd877d2c77	522	struct netif *netif;
andrewbonney	0:18dd877d2c77	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",
andrewbonney	0:18dd877d2c77	524	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
andrewbonney	0:18dd877d2c77	525	ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
andrewbonney	0:18dd877d2c77	526	ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
andrewbonney	0:18dd877d2c77	527
andrewbonney	0:18dd877d2c77	528	netif = ip_route(ipaddr);
andrewbonney	0:18dd877d2c77	529	if (netif == NULL) {
andrewbonney	0:18dd877d2c77	530	return ERR_RTE;
andrewbonney	0:18dd877d2c77	531	}
andrewbonney	0:18dd877d2c77	532
andrewbonney	0:18dd877d2c77	533	return update_arp_entry(netif, ipaddr, ethaddr, ETHARP_FLAG_TRY_HARD \| ETHARP_FLAG_STATIC_ENTRY);
andrewbonney	0:18dd877d2c77	534	}
andrewbonney	0:18dd877d2c77	535
andrewbonney	0:18dd877d2c77	536	/** Remove a static entry from the ARP table previously added with a call to
andrewbonney	0:18dd877d2c77	537	* etharp_add_static_entry.
andrewbonney	0:18dd877d2c77	538	*
andrewbonney	0:18dd877d2c77	539	* @param ipaddr IP address of the static entry to remove
andrewbonney	0:18dd877d2c77	540	* @return ERR_OK: entry removed
andrewbonney	0:18dd877d2c77	541	* ERR_MEM: entry wasn't found
andrewbonney	0:18dd877d2c77	542	* ERR_ARG: entry wasn't a static entry but a dynamic one
andrewbonney	0:18dd877d2c77	543	*/
andrewbonney	0:18dd877d2c77	544	err_t
andrewbonney	0:18dd877d2c77	545	etharp_remove_static_entry(ip_addr_t *ipaddr)
andrewbonney	0:18dd877d2c77	546	{
andrewbonney	0:18dd877d2c77	547	s8_t i;
andrewbonney	0:18dd877d2c77	548	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_remove_static_entry: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
andrewbonney	0:18dd877d2c77	549	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr)));
andrewbonney	0:18dd877d2c77	550
andrewbonney	0:18dd877d2c77	551	/* find or create ARP entry */
andrewbonney	0:18dd877d2c77	552	i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
andrewbonney	0:18dd877d2c77	553	/* bail out if no entry could be found */
andrewbonney	0:18dd877d2c77	554	if (i < 0) {
andrewbonney	0:18dd877d2c77	555	return (err_t)i;
andrewbonney	0:18dd877d2c77	556	}
andrewbonney	0:18dd877d2c77	557
andrewbonney	0:18dd877d2c77	558	if ((arp_table[i].state != ETHARP_STATE_STABLE) \|\|
andrewbonney	0:18dd877d2c77	559	(arp_table[i].static_entry == 0)) {
andrewbonney	0:18dd877d2c77	560	/* entry wasn't a static entry, cannot remove it */
andrewbonney	0:18dd877d2c77	561	return ERR_ARG;
andrewbonney	0:18dd877d2c77	562	}
andrewbonney	0:18dd877d2c77	563	/* entry found, free it */
andrewbonney	0:18dd877d2c77	564	free_entry(i);
andrewbonney	0:18dd877d2c77	565	return ERR_OK;
andrewbonney	0:18dd877d2c77	566	}
andrewbonney	0:18dd877d2c77	567	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
andrewbonney	0:18dd877d2c77	568
andrewbonney	0:18dd877d2c77	569	/**
andrewbonney	0:18dd877d2c77	570	* Finds (stable) ethernet/IP address pair from ARP table
andrewbonney	0:18dd877d2c77	571	* using interface and IP address index.
andrewbonney	0:18dd877d2c77	572	* @note the addresses in the ARP table are in network order!
andrewbonney	0:18dd877d2c77	573	*
andrewbonney	0:18dd877d2c77	574	* @param netif points to interface index
andrewbonney	0:18dd877d2c77	575	* @param ipaddr points to the (network order) IP address index
andrewbonney	0:18dd877d2c77	576	* @param eth_ret points to return pointer
andrewbonney	0:18dd877d2c77	577	* @param ip_ret points to return pointer
andrewbonney	0:18dd877d2c77	578	* @return table index if found, -1 otherwise
andrewbonney	0:18dd877d2c77	579	*/
andrewbonney	0:18dd877d2c77	580	s8_t
andrewbonney	0:18dd877d2c77	581	etharp_find_addr(struct netif netif, ip_addr_t ipaddr,
andrewbonney	0:18dd877d2c77	582	struct eth_addr eth_ret, ip_addr_t ip_ret)
andrewbonney	0:18dd877d2c77	583	{
andrewbonney	0:18dd877d2c77	584	s8_t i;
andrewbonney	0:18dd877d2c77	585
andrewbonney	0:18dd877d2c77	586	LWIP_ASSERT("eth_ret != NULL && ip_ret != NULL",
andrewbonney	0:18dd877d2c77	587	eth_ret != NULL && ip_ret != NULL);
andrewbonney	0:18dd877d2c77	588
andrewbonney	0:18dd877d2c77	589	LWIP_UNUSED_ARG(netif);
andrewbonney	0:18dd877d2c77	590
andrewbonney	0:18dd877d2c77	591	i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
andrewbonney	0:18dd877d2c77	592	if((i >= 0) && arp_table[i].state == ETHARP_STATE_STABLE) {
andrewbonney	0:18dd877d2c77	593	*eth_ret = &arp_table[i].ethaddr;
andrewbonney	0:18dd877d2c77	594	*ip_ret = &arp_table[i].ipaddr;
andrewbonney	0:18dd877d2c77	595	return i;
andrewbonney	0:18dd877d2c77	596	}
andrewbonney	0:18dd877d2c77	597	return -1;
andrewbonney	0:18dd877d2c77	598	}
andrewbonney	0:18dd877d2c77	599
andrewbonney	0:18dd877d2c77	600	#if ETHARP_TRUST_IP_MAC
andrewbonney	0:18dd877d2c77	601	/**
andrewbonney	0:18dd877d2c77	602	* Updates the ARP table using the given IP packet.
andrewbonney	0:18dd877d2c77	603	*
andrewbonney	0:18dd877d2c77	604	* Uses the incoming IP packet's source address to update the
andrewbonney	0:18dd877d2c77	605	* ARP cache for the local network. The function does not alter
andrewbonney	0:18dd877d2c77	606	* or free the packet. This function must be called before the
andrewbonney	0:18dd877d2c77	607	* packet p is passed to the IP layer.
andrewbonney	0:18dd877d2c77	608	*
andrewbonney	0:18dd877d2c77	609	* @param netif The lwIP network interface on which the IP packet pbuf arrived.
andrewbonney	0:18dd877d2c77	610	* @param p The IP packet that arrived on netif.
andrewbonney	0:18dd877d2c77	611	*
andrewbonney	0:18dd877d2c77	612	* @return NULL
andrewbonney	0:18dd877d2c77	613	*
andrewbonney	0:18dd877d2c77	614	* @see pbuf_free()
andrewbonney	0:18dd877d2c77	615	*/
andrewbonney	0:18dd877d2c77	616	static void
andrewbonney	0:18dd877d2c77	617	etharp_ip_input(struct netif netif, struct pbuf p)
andrewbonney	0:18dd877d2c77	618	{
andrewbonney	0:18dd877d2c77	619	struct eth_hdr *ethhdr;
andrewbonney	0:18dd877d2c77	620	struct ip_hdr *iphdr;
andrewbonney	0:18dd877d2c77	621	ip_addr_t iphdr_src;
andrewbonney	0:18dd877d2c77	622	LWIP_ERROR("netif != NULL", (netif != NULL), return;);
andrewbonney	0:18dd877d2c77	623
andrewbonney	0:18dd877d2c77	624	/* Only insert an entry if the source IP address of the
andrewbonney	0:18dd877d2c77	625	incoming IP packet comes from a host on the local network. */
andrewbonney	0:18dd877d2c77	626	ethhdr = (struct eth_hdr *)p->payload;
andrewbonney	0:18dd877d2c77	627	iphdr = (struct ip_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
andrewbonney	0:18dd877d2c77	628	#if ETHARP_SUPPORT_VLAN
andrewbonney	0:18dd877d2c77	629	if (ethhdr->type == ETHTYPE_VLAN) {
andrewbonney	0:18dd877d2c77	630	iphdr = (struct ip_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
andrewbonney	0:18dd877d2c77	631	}
andrewbonney	0:18dd877d2c77	632	#endif /* ETHARP_SUPPORT_VLAN */
andrewbonney	0:18dd877d2c77	633
andrewbonney	0:18dd877d2c77	634	ip_addr_copy(iphdr_src, iphdr->src);
andrewbonney	0:18dd877d2c77	635
andrewbonney	0:18dd877d2c77	636	/* source is not on the local network? */
andrewbonney	0:18dd877d2c77	637	if (!ip_addr_netcmp(&iphdr_src, &(netif->ip_addr), &(netif->netmask))) {
andrewbonney	0:18dd877d2c77	638	/* do nothing */
andrewbonney	0:18dd877d2c77	639	return;
andrewbonney	0:18dd877d2c77	640	}
andrewbonney	0:18dd877d2c77	641
andrewbonney	0:18dd877d2c77	642	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_ip_input: updating ETHARP table.\n"));
andrewbonney	0:18dd877d2c77	643	/* update the source IP address in the cache, if present */
andrewbonney	0:18dd877d2c77	644	/* @todo We could use ETHARP_FLAG_TRY_HARD if we think we are going to talk
andrewbonney	0:18dd877d2c77	645	* back soon (for example, if the destination IP address is ours. */
andrewbonney	0:18dd877d2c77	646	update_arp_entry(netif, &iphdr_src, &(ethhdr->src), ETHARP_FLAG_FIND_ONLY);
andrewbonney	0:18dd877d2c77	647	}
andrewbonney	0:18dd877d2c77	648	#endif /* ETHARP_TRUST_IP_MAC */
andrewbonney	0:18dd877d2c77	649
andrewbonney	0:18dd877d2c77	650	/**
andrewbonney	0:18dd877d2c77	651	* Responds to ARP requests to us. Upon ARP replies to us, add entry to cache
andrewbonney	0:18dd877d2c77	652	* send out queued IP packets. Updates cache with snooped address pairs.
andrewbonney	0:18dd877d2c77	653	*
andrewbonney	0:18dd877d2c77	654	* Should be called for incoming ARP packets. The pbuf in the argument
andrewbonney	0:18dd877d2c77	655	* is freed by this function.
andrewbonney	0:18dd877d2c77	656	*
andrewbonney	0:18dd877d2c77	657	* @param netif The lwIP network interface on which the ARP packet pbuf arrived.
andrewbonney	0:18dd877d2c77	658	* @param ethaddr Ethernet address of netif.
andrewbonney	0:18dd877d2c77	659	* @param p The ARP packet that arrived on netif. Is freed by this function.
andrewbonney	0:18dd877d2c77	660	*
andrewbonney	0:18dd877d2c77	661	* @return NULL
andrewbonney	0:18dd877d2c77	662	*
andrewbonney	0:18dd877d2c77	663	* @see pbuf_free()
andrewbonney	0:18dd877d2c77	664	*/
andrewbonney	0:18dd877d2c77	665	static void
andrewbonney	0:18dd877d2c77	666	etharp_arp_input(struct netif netif, struct eth_addr ethaddr, struct pbuf *p)
andrewbonney	0:18dd877d2c77	667	{
andrewbonney	0:18dd877d2c77	668	struct etharp_hdr *hdr;
andrewbonney	0:18dd877d2c77	669	struct eth_hdr *ethhdr;
andrewbonney	0:18dd877d2c77	670	/* these are aligned properly, whereas the ARP header fields might not be */
andrewbonney	0:18dd877d2c77	671	ip_addr_t sipaddr, dipaddr;
andrewbonney	0:18dd877d2c77	672	u8_t for_us;
andrewbonney	0:18dd877d2c77	673	#if LWIP_AUTOIP
andrewbonney	0:18dd877d2c77	674	const u8_t * ethdst_hwaddr;
andrewbonney	0:18dd877d2c77	675	#endif /* LWIP_AUTOIP */
andrewbonney	0:18dd877d2c77	676
andrewbonney	0:18dd877d2c77	677	LWIP_ERROR("netif != NULL", (netif != NULL), return;);
andrewbonney	0:18dd877d2c77	678
andrewbonney	0:18dd877d2c77	679	/* drop short ARP packets: we have to check for p->len instead of p->tot_len here
andrewbonney	0:18dd877d2c77	680	since a struct etharp_hdr is pointed to p->payload, so it musn't be chained! */
andrewbonney	0:18dd877d2c77	681	if (p->len < SIZEOF_ETHARP_PACKET) {
andrewbonney	0:18dd877d2c77	682	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_WARNING,
andrewbonney	0:18dd877d2c77	683	("etharp_arp_input: packet dropped, too short (%"S16_F"/%"S16_F")\n", p->tot_len,
andrewbonney	0:18dd877d2c77	684	(s16_t)SIZEOF_ETHARP_PACKET));
andrewbonney	0:18dd877d2c77	685	ETHARP_STATS_INC(etharp.lenerr);
andrewbonney	0:18dd877d2c77	686	ETHARP_STATS_INC(etharp.drop);
andrewbonney	0:18dd877d2c77	687	pbuf_free(p);
andrewbonney	0:18dd877d2c77	688	return;
andrewbonney	0:18dd877d2c77	689	}
andrewbonney	0:18dd877d2c77	690
andrewbonney	0:18dd877d2c77	691	ethhdr = (struct eth_hdr *)p->payload;
andrewbonney	0:18dd877d2c77	692	hdr = (struct etharp_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
andrewbonney	0:18dd877d2c77	693	#if ETHARP_SUPPORT_VLAN
andrewbonney	0:18dd877d2c77	694	if (ethhdr->type == ETHTYPE_VLAN) {
andrewbonney	0:18dd877d2c77	695	hdr = (struct etharp_hdr )(((u8_t)ethhdr) + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
andrewbonney	0:18dd877d2c77	696	}
andrewbonney	0:18dd877d2c77	697	#endif /* ETHARP_SUPPORT_VLAN */
andrewbonney	0:18dd877d2c77	698
andrewbonney	0:18dd877d2c77	699	/* RFC 826 "Packet Reception": */
andrewbonney	0:18dd877d2c77	700	if ((hdr->hwtype != PP_HTONS(HWTYPE_ETHERNET)) \|\|
andrewbonney	0:18dd877d2c77	701	(hdr->hwlen != ETHARP_HWADDR_LEN) \|\|
andrewbonney	0:18dd877d2c77	702	(hdr->protolen != sizeof(ip_addr_t)) \|\|
andrewbonney	0:18dd877d2c77	703	(hdr->proto != PP_HTONS(ETHTYPE_IP)) \|\|
andrewbonney	0:18dd877d2c77	704	(ethhdr->type != PP_HTONS(ETHTYPE_ARP))) {
andrewbonney	0:18dd877d2c77	705	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_WARNING,
andrewbonney	0:18dd877d2c77	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",
andrewbonney	0:18dd877d2c77	707	hdr->hwtype, hdr->hwlen, hdr->proto, hdr->protolen, ethhdr->type));
andrewbonney	0:18dd877d2c77	708	ETHARP_STATS_INC(etharp.proterr);
andrewbonney	0:18dd877d2c77	709	ETHARP_STATS_INC(etharp.drop);
andrewbonney	0:18dd877d2c77	710	pbuf_free(p);
andrewbonney	0:18dd877d2c77	711	return;
andrewbonney	0:18dd877d2c77	712	}
andrewbonney	0:18dd877d2c77	713	ETHARP_STATS_INC(etharp.recv);
andrewbonney	0:18dd877d2c77	714
andrewbonney	0:18dd877d2c77	715	#if LWIP_AUTOIP
andrewbonney	0:18dd877d2c77	716	/* We have to check if a host already has configured our random
andrewbonney	0:18dd877d2c77	717	* created link local address and continously check if there is
andrewbonney	0:18dd877d2c77	718	* a host with this IP-address so we can detect collisions */
andrewbonney	0:18dd877d2c77	719	autoip_arp_reply(netif, hdr);
andrewbonney	0:18dd877d2c77	720	#endif /* LWIP_AUTOIP */
andrewbonney	0:18dd877d2c77	721
andrewbonney	0:18dd877d2c77	722	/* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
andrewbonney	0:18dd877d2c77	723	* structure packing (not using structure copy which breaks strict-aliasing rules). */
andrewbonney	0:18dd877d2c77	724	IPADDR2_COPY(&sipaddr, &hdr->sipaddr);
andrewbonney	0:18dd877d2c77	725	IPADDR2_COPY(&dipaddr, &hdr->dipaddr);
andrewbonney	0:18dd877d2c77	726
andrewbonney	0:18dd877d2c77	727	/* this interface is not configured? */
andrewbonney	0:18dd877d2c77	728	if (ip_addr_isany(&netif->ip_addr)) {
andrewbonney	0:18dd877d2c77	729	for_us = 0;
andrewbonney	0:18dd877d2c77	730	} else {
andrewbonney	0:18dd877d2c77	731	/* ARP packet directed to us? */
andrewbonney	0:18dd877d2c77	732	for_us = (u8_t)ip_addr_cmp(&dipaddr, &(netif->ip_addr));
andrewbonney	0:18dd877d2c77	733	}
andrewbonney	0:18dd877d2c77	734
andrewbonney	0:18dd877d2c77	735	/* ARP message directed to us?
andrewbonney	0:18dd877d2c77	736	-> add IP address in ARP cache; assume requester wants to talk to us,
andrewbonney	0:18dd877d2c77	737	can result in directly sending the queued packets for this host.
andrewbonney	0:18dd877d2c77	738	ARP message not directed to us?
andrewbonney	0:18dd877d2c77	739	-> update the source IP address in the cache, if present */
andrewbonney	0:18dd877d2c77	740	update_arp_entry(netif, &sipaddr, &(hdr->shwaddr),
andrewbonney	0:18dd877d2c77	741	for_us ? ETHARP_FLAG_TRY_HARD : ETHARP_FLAG_FIND_ONLY);
andrewbonney	0:18dd877d2c77	742
andrewbonney	0:18dd877d2c77	743	/* now act on the message itself */
andrewbonney	0:18dd877d2c77	744	switch (hdr->opcode) {
andrewbonney	0:18dd877d2c77	745	/* ARP request? */
andrewbonney	0:18dd877d2c77	746	case PP_HTONS(ARP_REQUEST):
andrewbonney	0:18dd877d2c77	747	/* ARP request. If it asked for our address, we send out a
andrewbonney	0:18dd877d2c77	748	* reply. In any case, we time-stamp any existing ARP entry,
andrewbonney	0:18dd877d2c77	749	* and possiby send out an IP packet that was queued on it. */
andrewbonney	0:18dd877d2c77	750
andrewbonney	0:18dd877d2c77	751	LWIP_DEBUGF (ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP request\n"));
andrewbonney	0:18dd877d2c77	752	/* ARP request for our address? */
andrewbonney	0:18dd877d2c77	753	if (for_us) {
andrewbonney	0:18dd877d2c77	754
andrewbonney	0:18dd877d2c77	755	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: replying to ARP request for our IP address\n"));
andrewbonney	0:18dd877d2c77	756	/* Re-use pbuf to send ARP reply.
andrewbonney	0:18dd877d2c77	757	Since we are re-using an existing pbuf, we can't call etharp_raw since
andrewbonney	0:18dd877d2c77	758	that would allocate a new pbuf. */
andrewbonney	0:18dd877d2c77	759	hdr->opcode = htons(ARP_REPLY);
andrewbonney	0:18dd877d2c77	760
andrewbonney	0:18dd877d2c77	761	IPADDR2_COPY(&hdr->dipaddr, &hdr->sipaddr);
andrewbonney	0:18dd877d2c77	762	IPADDR2_COPY(&hdr->sipaddr, &netif->ip_addr);
andrewbonney	0:18dd877d2c77	763
andrewbonney	0:18dd877d2c77	764	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
andrewbonney	0:18dd877d2c77	765	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
andrewbonney	0:18dd877d2c77	766	#if LWIP_AUTOIP
andrewbonney	0:18dd877d2c77	767	/* If we are using Link-Local, all ARP packets that contain a Link-Local
andrewbonney	0:18dd877d2c77	768	* 'sender IP address' MUST be sent using link-layer broadcast instead of
andrewbonney	0:18dd877d2c77	769	* link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
andrewbonney	0:18dd877d2c77	770	ethdst_hwaddr = ip_addr_islinklocal(&netif->ip_addr) ? (u8_t*)(ethbroadcast.addr) : hdr->shwaddr.addr;
andrewbonney	0:18dd877d2c77	771	#endif /* LWIP_AUTOIP */
andrewbonney	0:18dd877d2c77	772
andrewbonney	0:18dd877d2c77	773	ETHADDR16_COPY(&hdr->dhwaddr, &hdr->shwaddr);
andrewbonney	0:18dd877d2c77	774	#if LWIP_AUTOIP
andrewbonney	0:18dd877d2c77	775	ETHADDR16_COPY(&ethhdr->dest, ethdst_hwaddr);
andrewbonney	0:18dd877d2c77	776	#else /* LWIP_AUTOIP */
andrewbonney	0:18dd877d2c77	777	ETHADDR16_COPY(&ethhdr->dest, &hdr->shwaddr);
andrewbonney	0:18dd877d2c77	778	#endif /* LWIP_AUTOIP */
andrewbonney	0:18dd877d2c77	779	ETHADDR16_COPY(&hdr->shwaddr, ethaddr);
andrewbonney	0:18dd877d2c77	780	ETHADDR16_COPY(&ethhdr->src, ethaddr);
andrewbonney	0:18dd877d2c77	781
andrewbonney	0:18dd877d2c77	782	/* hwtype, hwaddr_len, proto, protolen and the type in the ethernet header
andrewbonney	0:18dd877d2c77	783	are already correct, we tested that before */
andrewbonney	0:18dd877d2c77	784
andrewbonney	0:18dd877d2c77	785	/* return ARP reply */
andrewbonney	0:18dd877d2c77	786	netif->linkoutput(netif, p);
andrewbonney	0:18dd877d2c77	787	/* we are not configured? */
andrewbonney	0:18dd877d2c77	788	} else if (ip_addr_isany(&netif->ip_addr)) {
andrewbonney	0:18dd877d2c77	789	/* { for_us == 0 and netif->ip_addr.addr == 0 } */
andrewbonney	0:18dd877d2c77	790	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: we are unconfigured, ARP request ignored.\n"));
andrewbonney	0:18dd877d2c77	791	/* request was not directed to us */
andrewbonney	0:18dd877d2c77	792	} else {
andrewbonney	0:18dd877d2c77	793	/* { for_us == 0 and netif->ip_addr.addr != 0 } */
andrewbonney	0:18dd877d2c77	794	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: ARP request was not for us.\n"));
andrewbonney	0:18dd877d2c77	795	}
andrewbonney	0:18dd877d2c77	796	break;
andrewbonney	0:18dd877d2c77	797	case PP_HTONS(ARP_REPLY):
andrewbonney	0:18dd877d2c77	798	/* ARP reply. We already updated the ARP cache earlier. */
andrewbonney	0:18dd877d2c77	799	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP reply\n"));
andrewbonney	0:18dd877d2c77	800	#if (LWIP_DHCP && DHCP_DOES_ARP_CHECK)
andrewbonney	0:18dd877d2c77	801	/* DHCP wants to know about ARP replies from any host with an
andrewbonney	0:18dd877d2c77	802	* IP address also offered to us by the DHCP server. We do not
andrewbonney	0:18dd877d2c77	803	* want to take a duplicate IP address on a single network.
andrewbonney	0:18dd877d2c77	804	* @todo How should we handle redundant (fail-over) interfaces? */
andrewbonney	0:18dd877d2c77	805	dhcp_arp_reply(netif, &sipaddr);
andrewbonney	0:18dd877d2c77	806	#endif /* (LWIP_DHCP && DHCP_DOES_ARP_CHECK) */
andrewbonney	0:18dd877d2c77	807	break;
andrewbonney	0:18dd877d2c77	808	default:
andrewbonney	0:18dd877d2c77	809	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: ARP unknown opcode type %"S16_F"\n", htons(hdr->opcode)));
andrewbonney	0:18dd877d2c77	810	ETHARP_STATS_INC(etharp.err);
andrewbonney	0:18dd877d2c77	811	break;
andrewbonney	0:18dd877d2c77	812	}
andrewbonney	0:18dd877d2c77	813	/* free ARP packet */
andrewbonney	0:18dd877d2c77	814	pbuf_free(p);
andrewbonney	0:18dd877d2c77	815	}
andrewbonney	0:18dd877d2c77	816
andrewbonney	0:18dd877d2c77	817	/**
andrewbonney	0:18dd877d2c77	818	* Resolve and fill-in Ethernet address header for outgoing IP packet.
andrewbonney	0:18dd877d2c77	819	*
andrewbonney	0:18dd877d2c77	820	* For IP multicast and broadcast, corresponding Ethernet addresses
andrewbonney	0:18dd877d2c77	821	* are selected and the packet is transmitted on the link.
andrewbonney	0:18dd877d2c77	822	*
andrewbonney	0:18dd877d2c77	823	* For unicast addresses, the packet is submitted to etharp_query(). In
andrewbonney	0:18dd877d2c77	824	* case the IP address is outside the local network, the IP address of
andrewbonney	0:18dd877d2c77	825	* the gateway is used.
andrewbonney	0:18dd877d2c77	826	*
andrewbonney	0:18dd877d2c77	827	* @param netif The lwIP network interface which the IP packet will be sent on.
andrewbonney	0:18dd877d2c77	828	* @param q The pbuf(s) containing the IP packet to be sent.
andrewbonney	0:18dd877d2c77	829	* @param ipaddr The IP address of the packet destination.
andrewbonney	0:18dd877d2c77	830	*
andrewbonney	0:18dd877d2c77	831	* @return
andrewbonney	0:18dd877d2c77	832	* - ERR_RTE No route to destination (no gateway to external networks),
andrewbonney	0:18dd877d2c77	833	* or the return type of either etharp_query() or etharp_send_ip().
andrewbonney	0:18dd877d2c77	834	*/
andrewbonney	0:18dd877d2c77	835	err_t
andrewbonney	0:18dd877d2c77	836	etharp_output(struct netif netif, struct pbuf q, ip_addr_t *ipaddr)
andrewbonney	0:18dd877d2c77	837	{
andrewbonney	0:18dd877d2c77	838	struct eth_addr *dest, mcastaddr;
andrewbonney	0:18dd877d2c77	839
andrewbonney	0:18dd877d2c77	840	/* make room for Ethernet header - should not fail */
andrewbonney	0:18dd877d2c77	841	if (pbuf_header(q, sizeof(struct eth_hdr)) != 0) {
andrewbonney	0:18dd877d2c77	842	/* bail out */
andrewbonney	0:18dd877d2c77	843	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_SERIOUS,
andrewbonney	0:18dd877d2c77	844	("etharp_output: could not allocate room for header.\n"));
andrewbonney	0:18dd877d2c77	845	LINK_STATS_INC(link.lenerr);
andrewbonney	0:18dd877d2c77	846	return ERR_BUF;
andrewbonney	0:18dd877d2c77	847	}
andrewbonney	0:18dd877d2c77	848
andrewbonney	0:18dd877d2c77	849	/* assume unresolved Ethernet address */
andrewbonney	0:18dd877d2c77	850	dest = NULL;
andrewbonney	0:18dd877d2c77	851	/* Determine on destination hardware address. Broadcasts and multicasts
andrewbonney	0:18dd877d2c77	852	* are special, other IP addresses are looked up in the ARP table. */
andrewbonney	0:18dd877d2c77	853
andrewbonney	0:18dd877d2c77	854	/* broadcast destination IP address? */
andrewbonney	0:18dd877d2c77	855	if (ip_addr_isbroadcast(ipaddr, netif)) {
andrewbonney	0:18dd877d2c77	856	/* broadcast on Ethernet also */
andrewbonney	0:18dd877d2c77	857	dest = (struct eth_addr *)&ethbroadcast;
andrewbonney	0:18dd877d2c77	858	/* multicast destination IP address? */
andrewbonney	0:18dd877d2c77	859	} else if (ip_addr_ismulticast(ipaddr)) {
andrewbonney	0:18dd877d2c77	860	/* Hash IP multicast address to MAC address.*/
andrewbonney	0:18dd877d2c77	861	mcastaddr.addr[0] = 0x01;
andrewbonney	0:18dd877d2c77	862	mcastaddr.addr[1] = 0x00;
andrewbonney	0:18dd877d2c77	863	mcastaddr.addr[2] = 0x5e;
andrewbonney	0:18dd877d2c77	864	mcastaddr.addr[3] = ip4_addr2(ipaddr) & 0x7f;
andrewbonney	0:18dd877d2c77	865	mcastaddr.addr[4] = ip4_addr3(ipaddr);
andrewbonney	0:18dd877d2c77	866	mcastaddr.addr[5] = ip4_addr4(ipaddr);
andrewbonney	0:18dd877d2c77	867	/* destination Ethernet address is multicast */
andrewbonney	0:18dd877d2c77	868	dest = &mcastaddr;
andrewbonney	0:18dd877d2c77	869	/* unicast destination IP address? */
andrewbonney	0:18dd877d2c77	870	} else {
andrewbonney	0:18dd877d2c77	871	/* outside local network? */
andrewbonney	0:18dd877d2c77	872	if (!ip_addr_netcmp(ipaddr, &(netif->ip_addr), &(netif->netmask)) &&
andrewbonney	0:18dd877d2c77	873	!ip_addr_islinklocal(ipaddr)) {
andrewbonney	0:18dd877d2c77	874	/* interface has default gateway? */
andrewbonney	0:18dd877d2c77	875	if (!ip_addr_isany(&netif->gw)) {
andrewbonney	0:18dd877d2c77	876	/* send to hardware address of default gateway IP address */
andrewbonney	0:18dd877d2c77	877	ipaddr = &(netif->gw);
andrewbonney	0:18dd877d2c77	878	/* no default gateway available */
andrewbonney	0:18dd877d2c77	879	} else {
andrewbonney	0:18dd877d2c77	880	/* no route to destination error (default gateway missing) */
andrewbonney	0:18dd877d2c77	881	return ERR_RTE;
andrewbonney	0:18dd877d2c77	882	}
andrewbonney	0:18dd877d2c77	883	}
andrewbonney	0:18dd877d2c77	884	#if LWIP_NETIF_HWADDRHINT
andrewbonney	0:18dd877d2c77	885	if (netif->addr_hint != NULL) {
andrewbonney	0:18dd877d2c77	886	/* per-pcb cached entry was given */
andrewbonney	0:18dd877d2c77	887	u8_t etharp_cached_entry = *(netif->addr_hint);
andrewbonney	0:18dd877d2c77	888	if (etharp_cached_entry < ARP_TABLE_SIZE) {
andrewbonney	0:18dd877d2c77	889	#endif /* LWIP_NETIF_HWADDRHINT */
andrewbonney	0:18dd877d2c77	890	if ((arp_table[etharp_cached_entry].state == ETHARP_STATE_STABLE) &&
andrewbonney	0:18dd877d2c77	891	(ip_addr_cmp(ipaddr, &arp_table[etharp_cached_entry].ipaddr))) {
andrewbonney	0:18dd877d2c77	892	/* the per-pcb-cached entry is stable and the right one! */
andrewbonney	0:18dd877d2c77	893	ETHARP_STATS_INC(etharp.cachehit);
andrewbonney	0:18dd877d2c77	894	return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr),
andrewbonney	0:18dd877d2c77	895	&arp_table[etharp_cached_entry].ethaddr);
andrewbonney	0:18dd877d2c77	896	}
andrewbonney	0:18dd877d2c77	897	#if LWIP_NETIF_HWADDRHINT
andrewbonney	0:18dd877d2c77	898	}
andrewbonney	0:18dd877d2c77	899	}
andrewbonney	0:18dd877d2c77	900	#endif /* LWIP_NETIF_HWADDRHINT */
andrewbonney	0:18dd877d2c77	901	/* queue on destination Ethernet address belonging to ipaddr */
andrewbonney	0:18dd877d2c77	902	return etharp_query(netif, ipaddr, q);
andrewbonney	0:18dd877d2c77	903	}
andrewbonney	0:18dd877d2c77	904
andrewbonney	0:18dd877d2c77	905	/* continuation for multicast/broadcast destinations */
andrewbonney	0:18dd877d2c77	906	/* obtain source Ethernet address of the given interface */
andrewbonney	0:18dd877d2c77	907	/* send packet directly on the link */
andrewbonney	0:18dd877d2c77	908	return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr), dest);
andrewbonney	0:18dd877d2c77	909	}
andrewbonney	0:18dd877d2c77	910
andrewbonney	0:18dd877d2c77	911	/**
andrewbonney	0:18dd877d2c77	912	* Send an ARP request for the given IP address and/or queue a packet.
andrewbonney	0:18dd877d2c77	913	*
andrewbonney	0:18dd877d2c77	914	* If the IP address was not yet in the cache, a pending ARP cache entry
andrewbonney	0:18dd877d2c77	915	* is added and an ARP request is sent for the given address. The packet
andrewbonney	0:18dd877d2c77	916	* is queued on this entry.
andrewbonney	0:18dd877d2c77	917	*
andrewbonney	0:18dd877d2c77	918	* If the IP address was already pending in the cache, a new ARP request
andrewbonney	0:18dd877d2c77	919	* is sent for the given address. The packet is queued on this entry.
andrewbonney	0:18dd877d2c77	920	*
andrewbonney	0:18dd877d2c77	921	* If the IP address was already stable in the cache, and a packet is
andrewbonney	0:18dd877d2c77	922	* given, it is directly sent and no ARP request is sent out.
andrewbonney	0:18dd877d2c77	923	*
andrewbonney	0:18dd877d2c77	924	* If the IP address was already stable in the cache, and no packet is
andrewbonney	0:18dd877d2c77	925	* given, an ARP request is sent out.
andrewbonney	0:18dd877d2c77	926	*
andrewbonney	0:18dd877d2c77	927	* @param netif The lwIP network interface on which ipaddr
andrewbonney	0:18dd877d2c77	928	* must be queried for.
andrewbonney	0:18dd877d2c77	929	* @param ipaddr The IP address to be resolved.
andrewbonney	0:18dd877d2c77	930	* @param q If non-NULL, a pbuf that must be delivered to the IP address.
andrewbonney	0:18dd877d2c77	931	* q is not freed by this function.
andrewbonney	0:18dd877d2c77	932	*
andrewbonney	0:18dd877d2c77	933	* @note q must only be ONE packet, not a packet queue!
andrewbonney	0:18dd877d2c77	934	*
andrewbonney	0:18dd877d2c77	935	* @return
andrewbonney	0:18dd877d2c77	936	* - ERR_BUF Could not make room for Ethernet header.
andrewbonney	0:18dd877d2c77	937	* - ERR_MEM Hardware address unknown, and no more ARP entries available
andrewbonney	0:18dd877d2c77	938	* to query for address or queue the packet.
andrewbonney	0:18dd877d2c77	939	* - ERR_MEM Could not queue packet due to memory shortage.
andrewbonney	0:18dd877d2c77	940	* - ERR_RTE No route to destination (no gateway to external networks).
andrewbonney	0:18dd877d2c77	941	* - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
andrewbonney	0:18dd877d2c77	942	*
andrewbonney	0:18dd877d2c77	943	*/
andrewbonney	0:18dd877d2c77	944	err_t
andrewbonney	0:18dd877d2c77	945	etharp_query(struct netif netif, ip_addr_t ipaddr, struct pbuf *q)
andrewbonney	0:18dd877d2c77	946	{
andrewbonney	0:18dd877d2c77	947	struct eth_addr * srcaddr = (struct eth_addr *)netif->hwaddr;
andrewbonney	0:18dd877d2c77	948	err_t result = ERR_MEM;
andrewbonney	0:18dd877d2c77	949	s8_t i; /* ARP entry index */
andrewbonney	0:18dd877d2c77	950
andrewbonney	0:18dd877d2c77	951	/* non-unicast address? */
andrewbonney	0:18dd877d2c77	952	if (ip_addr_isbroadcast(ipaddr, netif) \|\|
andrewbonney	0:18dd877d2c77	953	ip_addr_ismulticast(ipaddr) \|\|
andrewbonney	0:18dd877d2c77	954	ip_addr_isany(ipaddr)) {
andrewbonney	0:18dd877d2c77	955	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: will not add non-unicast IP address to ARP cache\n"));
andrewbonney	0:18dd877d2c77	956	return ERR_ARG;
andrewbonney	0:18dd877d2c77	957	}
andrewbonney	0:18dd877d2c77	958
andrewbonney	0:18dd877d2c77	959	/* find entry in ARP cache, ask to create entry if queueing packet */
andrewbonney	0:18dd877d2c77	960	i = find_entry(ipaddr, ETHARP_FLAG_TRY_HARD);
andrewbonney	0:18dd877d2c77	961
andrewbonney	0:18dd877d2c77	962	/* could not find or create entry? */
andrewbonney	0:18dd877d2c77	963	if (i < 0) {
andrewbonney	0:18dd877d2c77	964	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: could not create ARP entry\n"));
andrewbonney	0:18dd877d2c77	965	if (q) {
andrewbonney	0:18dd877d2c77	966	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: packet dropped\n"));
andrewbonney	0:18dd877d2c77	967	ETHARP_STATS_INC(etharp.memerr);
andrewbonney	0:18dd877d2c77	968	}
andrewbonney	0:18dd877d2c77	969	return (err_t)i;
andrewbonney	0:18dd877d2c77	970	}
andrewbonney	0:18dd877d2c77	971
andrewbonney	0:18dd877d2c77	972	/* mark a fresh entry as pending (we just sent a request) */
andrewbonney	0:18dd877d2c77	973	if (arp_table[i].state == ETHARP_STATE_EMPTY) {
andrewbonney	0:18dd877d2c77	974	arp_table[i].state = ETHARP_STATE_PENDING;
andrewbonney	0:18dd877d2c77	975	}
andrewbonney	0:18dd877d2c77	976
andrewbonney	0:18dd877d2c77	977	/* { i is either a STABLE or (new or existing) PENDING entry } */
andrewbonney	0:18dd877d2c77	978	LWIP_ASSERT("arp_table[i].state == PENDING or STABLE",
andrewbonney	0:18dd877d2c77	979	((arp_table[i].state == ETHARP_STATE_PENDING) \|\|
andrewbonney	0:18dd877d2c77	980	(arp_table[i].state == ETHARP_STATE_STABLE)));
andrewbonney	0:18dd877d2c77	981
andrewbonney	0:18dd877d2c77	982	/* do we have a pending entry? or an implicit query request? */
andrewbonney	0:18dd877d2c77	983	if ((arp_table[i].state == ETHARP_STATE_PENDING) \|\| (q == NULL)) {
andrewbonney	0:18dd877d2c77	984	/* try to resolve it; send out ARP request */
andrewbonney	0:18dd877d2c77	985	result = etharp_request(netif, ipaddr);
andrewbonney	0:18dd877d2c77	986	if (result != ERR_OK) {
andrewbonney	0:18dd877d2c77	987	/* ARP request couldn't be sent */
andrewbonney	0:18dd877d2c77	988	/* We don't re-send arp request in etharp_tmr, but we still queue packets,
andrewbonney	0:18dd877d2c77	989	since this failure could be temporary, and the next packet calling
andrewbonney	0:18dd877d2c77	990	etharp_query again could lead to sending the queued packets. */
andrewbonney	0:18dd877d2c77	991	}
andrewbonney	0:18dd877d2c77	992	if (q == NULL) {
andrewbonney	0:18dd877d2c77	993	return result;
andrewbonney	0:18dd877d2c77	994	}
andrewbonney	0:18dd877d2c77	995	}
andrewbonney	0:18dd877d2c77	996
andrewbonney	0:18dd877d2c77	997	/* packet given? */
andrewbonney	0:18dd877d2c77	998	LWIP_ASSERT("q != NULL", q != NULL);
andrewbonney	0:18dd877d2c77	999	/* stable entry? */
andrewbonney	0:18dd877d2c77	1000	if (arp_table[i].state == ETHARP_STATE_STABLE) {
andrewbonney	0:18dd877d2c77	1001	/* we have a valid IP->Ethernet address mapping */
andrewbonney	0:18dd877d2c77	1002	ETHARP_SET_HINT(netif, i);
andrewbonney	0:18dd877d2c77	1003	/* send the packet */
andrewbonney	0:18dd877d2c77	1004	result = etharp_send_ip(netif, q, srcaddr, &(arp_table[i].ethaddr));
andrewbonney	0:18dd877d2c77	1005	/* pending entry? (either just created or already pending */
andrewbonney	0:18dd877d2c77	1006	} else if (arp_table[i].state == ETHARP_STATE_PENDING) {
andrewbonney	0:18dd877d2c77	1007	#if ARP_QUEUEING /* queue the given q packet */
andrewbonney	0:18dd877d2c77	1008	struct pbuf *p;
andrewbonney	0:18dd877d2c77	1009	int copy_needed = 0;
andrewbonney	0:18dd877d2c77	1010	/* IF q includes a PBUF_REF, PBUF_POOL or PBUF_RAM, we have no choice but
andrewbonney	0:18dd877d2c77	1011	* to copy the whole queue into a new PBUF_RAM (see bug #11400)
andrewbonney	0:18dd877d2c77	1012	* PBUF_ROMs can be left as they are, since ROM must not get changed. */
andrewbonney	0:18dd877d2c77	1013	p = q;
andrewbonney	0:18dd877d2c77	1014	while (p) {
andrewbonney	0:18dd877d2c77	1015	LWIP_ASSERT("no packet queues allowed!", (p->len != p->tot_len) \|\| (p->next == 0));
andrewbonney	0:18dd877d2c77	1016	if(p->type != PBUF_ROM) {
andrewbonney	0:18dd877d2c77	1017	copy_needed = 1;
andrewbonney	0:18dd877d2c77	1018	break;
andrewbonney	0:18dd877d2c77	1019	}
andrewbonney	0:18dd877d2c77	1020	p = p->next;
andrewbonney	0:18dd877d2c77	1021	}
andrewbonney	0:18dd877d2c77	1022	if(copy_needed) {
andrewbonney	0:18dd877d2c77	1023	/* copy the whole packet into new pbufs */
andrewbonney	0:18dd877d2c77	1024	p = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
andrewbonney	0:18dd877d2c77	1025	if(p != NULL) {
andrewbonney	0:18dd877d2c77	1026	if (pbuf_copy(p, q) != ERR_OK) {
andrewbonney	0:18dd877d2c77	1027	pbuf_free(p);
andrewbonney	0:18dd877d2c77	1028	p = NULL;
andrewbonney	0:18dd877d2c77	1029	}
andrewbonney	0:18dd877d2c77	1030	}
andrewbonney	0:18dd877d2c77	1031	} else {
andrewbonney	0:18dd877d2c77	1032	/* referencing the old pbuf is enough */
andrewbonney	0:18dd877d2c77	1033	p = q;
andrewbonney	0:18dd877d2c77	1034	pbuf_ref(p);
andrewbonney	0:18dd877d2c77	1035	}
andrewbonney	0:18dd877d2c77	1036	/* packet could be taken over? */
andrewbonney	0:18dd877d2c77	1037	if (p != NULL) {
andrewbonney	0:18dd877d2c77	1038	/* queue packet ... */
andrewbonney	0:18dd877d2c77	1039	struct etharp_q_entry *new_entry;
andrewbonney	0:18dd877d2c77	1040	/* allocate a new arp queue entry */
andrewbonney	0:18dd877d2c77	1041	new_entry = (struct etharp_q_entry *)memp_malloc(MEMP_ARP_QUEUE);
andrewbonney	0:18dd877d2c77	1042	if (new_entry != NULL) {
andrewbonney	0:18dd877d2c77	1043	new_entry->next = 0;
andrewbonney	0:18dd877d2c77	1044	new_entry->p = p;
andrewbonney	0:18dd877d2c77	1045	if(arp_table[i].q != NULL) {
andrewbonney	0:18dd877d2c77	1046	/* queue was already existent, append the new entry to the end */
andrewbonney	0:18dd877d2c77	1047	struct etharp_q_entry *r;
andrewbonney	0:18dd877d2c77	1048	r = arp_table[i].q;
andrewbonney	0:18dd877d2c77	1049	while (r->next != NULL) {
andrewbonney	0:18dd877d2c77	1050	r = r->next;
andrewbonney	0:18dd877d2c77	1051	}
andrewbonney	0:18dd877d2c77	1052	r->next = new_entry;
andrewbonney	0:18dd877d2c77	1053	} else {
andrewbonney	0:18dd877d2c77	1054	/* queue did not exist, first item in queue */
andrewbonney	0:18dd877d2c77	1055	arp_table[i].q = new_entry;
andrewbonney	0:18dd877d2c77	1056	}
andrewbonney	0:18dd877d2c77	1057	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: queued packet %p on ARP entry %"S16_F"\n", (void *)q, (s16_t)i));
andrewbonney	0:18dd877d2c77	1058	result = ERR_OK;
andrewbonney	0:18dd877d2c77	1059	} else {
andrewbonney	0:18dd877d2c77	1060	/* the pool MEMP_ARP_QUEUE is empty */
andrewbonney	0:18dd877d2c77	1061	pbuf_free(p);
andrewbonney	0:18dd877d2c77	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));
andrewbonney	0:18dd877d2c77	1063	/* { result == ERR_MEM } through initialization */
andrewbonney	0:18dd877d2c77	1064	}
andrewbonney	0:18dd877d2c77	1065	} else {
andrewbonney	0:18dd877d2c77	1066	ETHARP_STATS_INC(etharp.memerr);
andrewbonney	0:18dd877d2c77	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));
andrewbonney	0:18dd877d2c77	1068	/* { result == ERR_MEM } through initialization */
andrewbonney	0:18dd877d2c77	1069	}
andrewbonney	0:18dd877d2c77	1070	#else /* ARP_QUEUEING */
andrewbonney	0:18dd877d2c77	1071	/* q && state == PENDING && ARP_QUEUEING == 0 => result = ERR_MEM */
andrewbonney	0:18dd877d2c77	1072	/* { result == ERR_MEM } through initialization */
andrewbonney	0:18dd877d2c77	1073	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: Ethernet destination address unknown, queueing disabled, packet %p dropped\n", (void *)q));
andrewbonney	0:18dd877d2c77	1074	#endif /* ARP_QUEUEING */
andrewbonney	0:18dd877d2c77	1075	}
andrewbonney	0:18dd877d2c77	1076	return result;
andrewbonney	0:18dd877d2c77	1077	}
andrewbonney	0:18dd877d2c77	1078
andrewbonney	0:18dd877d2c77	1079	/**
andrewbonney	0:18dd877d2c77	1080	* Send a raw ARP packet (opcode and all addresses can be modified)
andrewbonney	0:18dd877d2c77	1081	*
andrewbonney	0:18dd877d2c77	1082	* @param netif the lwip network interface on which to send the ARP packet
andrewbonney	0:18dd877d2c77	1083	* @param ethsrc_addr the source MAC address for the ethernet header
andrewbonney	0:18dd877d2c77	1084	* @param ethdst_addr the destination MAC address for the ethernet header
andrewbonney	0:18dd877d2c77	1085	* @param hwsrc_addr the source MAC address for the ARP protocol header
andrewbonney	0:18dd877d2c77	1086	* @param ipsrc_addr the source IP address for the ARP protocol header
andrewbonney	0:18dd877d2c77	1087	* @param hwdst_addr the destination MAC address for the ARP protocol header
andrewbonney	0:18dd877d2c77	1088	* @param ipdst_addr the destination IP address for the ARP protocol header
andrewbonney	0:18dd877d2c77	1089	* @param opcode the type of the ARP packet
andrewbonney	0:18dd877d2c77	1090	* @return ERR_OK if the ARP packet has been sent
andrewbonney	0:18dd877d2c77	1091	* ERR_MEM if the ARP packet couldn't be allocated
andrewbonney	0:18dd877d2c77	1092	* any other err_t on failure
andrewbonney	0:18dd877d2c77	1093	*/
andrewbonney	0:18dd877d2c77	1094	#if !LWIP_AUTOIP
andrewbonney	0:18dd877d2c77	1095	static
andrewbonney	0:18dd877d2c77	1096	#endif /* LWIP_AUTOIP */
andrewbonney	0:18dd877d2c77	1097	err_t
andrewbonney	0:18dd877d2c77	1098	etharp_raw(struct netif netif, const struct eth_addr ethsrc_addr,
andrewbonney	0:18dd877d2c77	1099	const struct eth_addr *ethdst_addr,
andrewbonney	0:18dd877d2c77	1100	const struct eth_addr hwsrc_addr, const ip_addr_t ipsrc_addr,
andrewbonney	0:18dd877d2c77	1101	const struct eth_addr hwdst_addr, const ip_addr_t ipdst_addr,
andrewbonney	0:18dd877d2c77	1102	const u16_t opcode)
andrewbonney	0:18dd877d2c77	1103	{
andrewbonney	0:18dd877d2c77	1104	struct pbuf *p;
andrewbonney	0:18dd877d2c77	1105	err_t result = ERR_OK;
andrewbonney	0:18dd877d2c77	1106	struct eth_hdr *ethhdr;
andrewbonney	0:18dd877d2c77	1107	struct etharp_hdr *hdr;
andrewbonney	0:18dd877d2c77	1108	#if LWIP_AUTOIP
andrewbonney	0:18dd877d2c77	1109	const u8_t * ethdst_hwaddr;
andrewbonney	0:18dd877d2c77	1110	#endif /* LWIP_AUTOIP */
andrewbonney	0:18dd877d2c77	1111
andrewbonney	0:18dd877d2c77	1112	/* allocate a pbuf for the outgoing ARP request packet */
andrewbonney	0:18dd877d2c77	1113	p = pbuf_alloc(PBUF_RAW, SIZEOF_ETHARP_PACKET, PBUF_RAM);
andrewbonney	0:18dd877d2c77	1114	/* could allocate a pbuf for an ARP request? */
andrewbonney	0:18dd877d2c77	1115	if (p == NULL) {
andrewbonney	0:18dd877d2c77	1116	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_SERIOUS,
andrewbonney	0:18dd877d2c77	1117	("etharp_raw: could not allocate pbuf for ARP request.\n"));
andrewbonney	0:18dd877d2c77	1118	ETHARP_STATS_INC(etharp.memerr);
andrewbonney	0:18dd877d2c77	1119	return ERR_MEM;
andrewbonney	0:18dd877d2c77	1120	}
andrewbonney	0:18dd877d2c77	1121	LWIP_ASSERT("check that first pbuf can hold struct etharp_hdr",
andrewbonney	0:18dd877d2c77	1122	(p->len >= SIZEOF_ETHARP_PACKET));
andrewbonney	0:18dd877d2c77	1123
andrewbonney	0:18dd877d2c77	1124	ethhdr = (struct eth_hdr *)p->payload;
andrewbonney	0:18dd877d2c77	1125	hdr = (struct etharp_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
andrewbonney	0:18dd877d2c77	1126	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_raw: sending raw ARP packet.\n"));
andrewbonney	0:18dd877d2c77	1127	hdr->opcode = htons(opcode);
andrewbonney	0:18dd877d2c77	1128
andrewbonney	0:18dd877d2c77	1129	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
andrewbonney	0:18dd877d2c77	1130	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
andrewbonney	0:18dd877d2c77	1131	#if LWIP_AUTOIP
andrewbonney	0:18dd877d2c77	1132	/* If we are using Link-Local, all ARP packets that contain a Link-Local
andrewbonney	0:18dd877d2c77	1133	* 'sender IP address' MUST be sent using link-layer broadcast instead of
andrewbonney	0:18dd877d2c77	1134	* link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
andrewbonney	0:18dd877d2c77	1135	ethdst_hwaddr = ip_addr_islinklocal(ipsrc_addr) ? (u8_t*)(ethbroadcast.addr) : ethdst_addr->addr;
andrewbonney	0:18dd877d2c77	1136	#endif /* LWIP_AUTOIP */
andrewbonney	0:18dd877d2c77	1137	/* Write the ARP MAC-Addresses */
andrewbonney	0:18dd877d2c77	1138	ETHADDR16_COPY(&hdr->shwaddr, hwsrc_addr);
andrewbonney	0:18dd877d2c77	1139	ETHADDR16_COPY(&hdr->dhwaddr, hwdst_addr);
andrewbonney	0:18dd877d2c77	1140	/* Write the Ethernet MAC-Addresses */
andrewbonney	0:18dd877d2c77	1141	#if LWIP_AUTOIP
andrewbonney	0:18dd877d2c77	1142	ETHADDR16_COPY(&ethhdr->dest, ethdst_hwaddr);
andrewbonney	0:18dd877d2c77	1143	#else /* LWIP_AUTOIP */
andrewbonney	0:18dd877d2c77	1144	ETHADDR16_COPY(&ethhdr->dest, ethdst_addr);
andrewbonney	0:18dd877d2c77	1145	#endif /* LWIP_AUTOIP */
andrewbonney	0:18dd877d2c77	1146	ETHADDR16_COPY(&ethhdr->src, ethsrc_addr);
andrewbonney	0:18dd877d2c77	1147	/* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
andrewbonney	0:18dd877d2c77	1148	* structure packing. */
andrewbonney	0:18dd877d2c77	1149	IPADDR2_COPY(&hdr->sipaddr, ipsrc_addr);
andrewbonney	0:18dd877d2c77	1150	IPADDR2_COPY(&hdr->dipaddr, ipdst_addr);
andrewbonney	0:18dd877d2c77	1151
andrewbonney	0:18dd877d2c77	1152	hdr->hwtype = PP_HTONS(HWTYPE_ETHERNET);
andrewbonney	0:18dd877d2c77	1153	hdr->proto = PP_HTONS(ETHTYPE_IP);
andrewbonney	0:18dd877d2c77	1154	/* set hwlen and protolen */
andrewbonney	0:18dd877d2c77	1155	hdr->hwlen = ETHARP_HWADDR_LEN;
andrewbonney	0:18dd877d2c77	1156	hdr->protolen = sizeof(ip_addr_t);
andrewbonney	0:18dd877d2c77	1157
andrewbonney	0:18dd877d2c77	1158	ethhdr->type = PP_HTONS(ETHTYPE_ARP);
andrewbonney	0:18dd877d2c77	1159	/* send ARP query */
andrewbonney	0:18dd877d2c77	1160	result = netif->linkoutput(netif, p);
andrewbonney	0:18dd877d2c77	1161	ETHARP_STATS_INC(etharp.xmit);
andrewbonney	0:18dd877d2c77	1162	/* free ARP query packet */
andrewbonney	0:18dd877d2c77	1163	pbuf_free(p);
andrewbonney	0:18dd877d2c77	1164	p = NULL;
andrewbonney	0:18dd877d2c77	1165	/* could not allocate pbuf for ARP request */
andrewbonney	0:18dd877d2c77	1166
andrewbonney	0:18dd877d2c77	1167	return result;
andrewbonney	0:18dd877d2c77	1168	}
andrewbonney	0:18dd877d2c77	1169
andrewbonney	0:18dd877d2c77	1170	/**
andrewbonney	0:18dd877d2c77	1171	* Send an ARP request packet asking for ipaddr.
andrewbonney	0:18dd877d2c77	1172	*
andrewbonney	0:18dd877d2c77	1173	* @param netif the lwip network interface on which to send the request
andrewbonney	0:18dd877d2c77	1174	* @param ipaddr the IP address for which to ask
andrewbonney	0:18dd877d2c77	1175	* @return ERR_OK if the request has been sent
andrewbonney	0:18dd877d2c77	1176	* ERR_MEM if the ARP packet couldn't be allocated
andrewbonney	0:18dd877d2c77	1177	* any other err_t on failure
andrewbonney	0:18dd877d2c77	1178	*/
andrewbonney	0:18dd877d2c77	1179	err_t
andrewbonney	0:18dd877d2c77	1180	etharp_request(struct netif netif, ip_addr_t ipaddr)
andrewbonney	0:18dd877d2c77	1181	{
andrewbonney	0:18dd877d2c77	1182	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_request: sending ARP request.\n"));
andrewbonney	0:18dd877d2c77	1183	return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, &ethbroadcast,
andrewbonney	0:18dd877d2c77	1184	(struct eth_addr *)netif->hwaddr, &netif->ip_addr, &ethzero,
andrewbonney	0:18dd877d2c77	1185	ipaddr, ARP_REQUEST);
andrewbonney	0:18dd877d2c77	1186	}
andrewbonney	0:18dd877d2c77	1187	#endif /* LWIP_ARP */
andrewbonney	0:18dd877d2c77	1188
andrewbonney	0:18dd877d2c77	1189	/**
andrewbonney	0:18dd877d2c77	1190	* Process received ethernet frames. Using this function instead of directly
andrewbonney	0:18dd877d2c77	1191	* calling ip_input and passing ARP frames through etharp in ethernetif_input,
andrewbonney	0:18dd877d2c77	1192	* the ARP cache is protected from concurrent access.
andrewbonney	0:18dd877d2c77	1193	*
andrewbonney	0:18dd877d2c77	1194	* @param p the recevied packet, p->payload pointing to the ethernet header
andrewbonney	0:18dd877d2c77	1195	* @param netif the network interface on which the packet was received
andrewbonney	0:18dd877d2c77	1196	*/
andrewbonney	0:18dd877d2c77	1197	err_t
andrewbonney	0:18dd877d2c77	1198	ethernet_input(struct pbuf p, struct netif netif)
andrewbonney	0:18dd877d2c77	1199	{
andrewbonney	0:18dd877d2c77	1200	struct eth_hdr* ethhdr;
andrewbonney	0:18dd877d2c77	1201	u16_t type;
andrewbonney	0:18dd877d2c77	1202
andrewbonney	0:18dd877d2c77	1203	/* points to packet payload, which starts with an Ethernet header */
andrewbonney	0:18dd877d2c77	1204	ethhdr = (struct eth_hdr *)p->payload;
andrewbonney	0:18dd877d2c77	1205	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE,
andrewbonney	0:18dd877d2c77	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",
andrewbonney	0:18dd877d2c77	1207	(unsigned)ethhdr->dest.addr[0], (unsigned)ethhdr->dest.addr[1], (unsigned)ethhdr->dest.addr[2],
andrewbonney	0:18dd877d2c77	1208	(unsigned)ethhdr->dest.addr[3], (unsigned)ethhdr->dest.addr[4], (unsigned)ethhdr->dest.addr[5],
andrewbonney	0:18dd877d2c77	1209	(unsigned)ethhdr->src.addr[0], (unsigned)ethhdr->src.addr[1], (unsigned)ethhdr->src.addr[2],
andrewbonney	0:18dd877d2c77	1210	(unsigned)ethhdr->src.addr[3], (unsigned)ethhdr->src.addr[4], (unsigned)ethhdr->src.addr[5],
andrewbonney	0:18dd877d2c77	1211	(unsigned)htons(ethhdr->type)));
andrewbonney	0:18dd877d2c77	1212
andrewbonney	0:18dd877d2c77	1213	type = ethhdr->type;
andrewbonney	0:18dd877d2c77	1214	#if ETHARP_SUPPORT_VLAN
andrewbonney	0:18dd877d2c77	1215	if (type == PP_HTONS(ETHTYPE_VLAN)) {
andrewbonney	0:18dd877d2c77	1216	struct eth_vlan_hdr vlan = (struct eth_vlan_hdr)(((char*)ethhdr) + SIZEOF_ETH_HDR);
andrewbonney	0:18dd877d2c77	1217	#ifdef ETHARP_VLAN_CHECK /* if not, allow all VLANs */
andrewbonney	0:18dd877d2c77	1218	if (VLAN_ID(vlan) != ETHARP_VLAN_CHECK) {
andrewbonney	0:18dd877d2c77	1219	/* silently ignore this packet: not for our VLAN */
andrewbonney	0:18dd877d2c77	1220	pbuf_free(p);
andrewbonney	0:18dd877d2c77	1221	return ERR_OK;
andrewbonney	0:18dd877d2c77	1222	}
andrewbonney	0:18dd877d2c77	1223	#endif /* ETHARP_VLAN_CHECK */
andrewbonney	0:18dd877d2c77	1224	type = vlan->tpid;
andrewbonney	0:18dd877d2c77	1225	}
andrewbonney	0:18dd877d2c77	1226	#endif /* ETHARP_SUPPORT_VLAN */
andrewbonney	0:18dd877d2c77	1227
andrewbonney	0:18dd877d2c77	1228	#if LWIP_ARP_FILTER_NETIF
andrewbonney	0:18dd877d2c77	1229	netif = LWIP_ARP_FILTER_NETIF_FN(p, netif, htons(type));
andrewbonney	0:18dd877d2c77	1230	#endif /* LWIP_ARP_FILTER_NETIF*/
andrewbonney	0:18dd877d2c77	1231
andrewbonney	0:18dd877d2c77	1232	switch (type) {
andrewbonney	0:18dd877d2c77	1233	#if LWIP_ARP
andrewbonney	0:18dd877d2c77	1234	/* IP packet? */
andrewbonney	0:18dd877d2c77	1235	case PP_HTONS(ETHTYPE_IP):
andrewbonney	0:18dd877d2c77	1236	if (!(netif->flags & NETIF_FLAG_ETHARP)) {
andrewbonney	0:18dd877d2c77	1237	goto free_and_return;
andrewbonney	0:18dd877d2c77	1238	}
andrewbonney	0:18dd877d2c77	1239	#if ETHARP_TRUST_IP_MAC
andrewbonney	0:18dd877d2c77	1240	/* update ARP table */
andrewbonney	0:18dd877d2c77	1241	etharp_ip_input(netif, p);
andrewbonney	0:18dd877d2c77	1242	#endif /* ETHARP_TRUST_IP_MAC */
andrewbonney	0:18dd877d2c77	1243	/* skip Ethernet header */
andrewbonney	0:18dd877d2c77	1244	if(pbuf_header(p, -(s16_t)SIZEOF_ETH_HDR)) {
andrewbonney	0:18dd877d2c77	1245	LWIP_ASSERT("Can't move over header in packet", 0);
andrewbonney	0:18dd877d2c77	1246	goto free_and_return;
andrewbonney	0:18dd877d2c77	1247	} else {
andrewbonney	0:18dd877d2c77	1248	/* pass to IP layer */
andrewbonney	0:18dd877d2c77	1249	ip_input(p, netif);
andrewbonney	0:18dd877d2c77	1250	}
andrewbonney	0:18dd877d2c77	1251	break;
andrewbonney	0:18dd877d2c77	1252
andrewbonney	0:18dd877d2c77	1253	case PP_HTONS(ETHTYPE_ARP):
andrewbonney	0:18dd877d2c77	1254	if (!(netif->flags & NETIF_FLAG_ETHARP)) {
andrewbonney	0:18dd877d2c77	1255	goto free_and_return;
andrewbonney	0:18dd877d2c77	1256	}
andrewbonney	0:18dd877d2c77	1257	/* pass p to ARP module */
andrewbonney	0:18dd877d2c77	1258	etharp_arp_input(netif, (struct eth_addr*)(netif->hwaddr), p);
andrewbonney	0:18dd877d2c77	1259	break;
andrewbonney	0:18dd877d2c77	1260	#endif /* LWIP_ARP */
andrewbonney	0:18dd877d2c77	1261	#if PPPOE_SUPPORT
andrewbonney	0:18dd877d2c77	1262	case PP_HTONS(ETHTYPE_PPPOEDISC): /* PPP Over Ethernet Discovery Stage */
andrewbonney	0:18dd877d2c77	1263	pppoe_disc_input(netif, p);
andrewbonney	0:18dd877d2c77	1264	break;
andrewbonney	0:18dd877d2c77	1265
andrewbonney	0:18dd877d2c77	1266	case PP_HTONS(ETHTYPE_PPPOE): /* PPP Over Ethernet Session Stage */
andrewbonney	0:18dd877d2c77	1267	pppoe_data_input(netif, p);
andrewbonney	0:18dd877d2c77	1268	break;
andrewbonney	0:18dd877d2c77	1269	#endif /* PPPOE_SUPPORT */
andrewbonney	0:18dd877d2c77	1270
andrewbonney	0:18dd877d2c77	1271	default:
andrewbonney	0:18dd877d2c77	1272	ETHARP_STATS_INC(etharp.proterr);
andrewbonney	0:18dd877d2c77	1273	ETHARP_STATS_INC(etharp.drop);
andrewbonney	0:18dd877d2c77	1274	goto free_and_return;
andrewbonney	0:18dd877d2c77	1275	}
andrewbonney	0:18dd877d2c77	1276
andrewbonney	0:18dd877d2c77	1277	/* This means the pbuf is freed or consumed,
andrewbonney	0:18dd877d2c77	1278	so the caller doesn't have to free it again */
andrewbonney	0:18dd877d2c77	1279	return ERR_OK;
andrewbonney	0:18dd877d2c77	1280
andrewbonney	0:18dd877d2c77	1281	free_and_return:
andrewbonney	0:18dd877d2c77	1282	pbuf_free(p);
andrewbonney	0:18dd877d2c77	1283	return ERR_OK;
andrewbonney	0:18dd877d2c77	1284	}
andrewbonney	0:18dd877d2c77	1285	#endif /* LWIP_ARP \|\| LWIP_ETHERNET */

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Type:	Library
Created:	26 May 2011
Imports:	33
Forks:	0
Commits:	1
Dependents:	0
Dependencies:	0
Followers:	1

lwip/netif/etharp.c@0:18dd877d2c77, 2011-05-26 (annotated)

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