NetServicesSource - Experimental HTTPClient with proxy support

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Experimental HTTPClient with proxy support

lwip/netif/etharp.c@0:b56b6a05cad4, 2011-06-29 (annotated)

Committer:: igorsk
Date:: Wed Jun 29 16:01:58 2011 +0000
Revision:: 0:b56b6a05cad4

Who changed what in which revision?

User	Revision	Line number	New contents of line
igorsk	0:b56b6a05cad4	1	/**
igorsk	0:b56b6a05cad4	2	* @file
igorsk	0:b56b6a05cad4	3	* Address Resolution Protocol module for IP over Ethernet
igorsk	0:b56b6a05cad4	4	*
igorsk	0:b56b6a05cad4	5	* Functionally, ARP is divided into two parts. The first maps an IP address
igorsk	0:b56b6a05cad4	6	* to a physical address when sending a packet, and the second part answers
igorsk	0:b56b6a05cad4	7	* requests from other machines for our physical address.
igorsk	0:b56b6a05cad4	8	*
igorsk	0:b56b6a05cad4	9	* This implementation complies with RFC 826 (Ethernet ARP). It supports
igorsk	0:b56b6a05cad4	10	* Gratuitious ARP from RFC3220 (IP Mobility Support for IPv4) section 4.6
igorsk	0:b56b6a05cad4	11	* if an interface calls etharp_gratuitous(our_netif) upon address change.
igorsk	0:b56b6a05cad4	12	*/
igorsk	0:b56b6a05cad4	13
igorsk	0:b56b6a05cad4	14	/*
igorsk	0:b56b6a05cad4	15	* Copyright (c) 2001-2003 Swedish Institute of Computer Science.
igorsk	0:b56b6a05cad4	16	* Copyright (c) 2003-2004 Leon Woestenberg <leon.woestenberg@axon.tv>
igorsk	0:b56b6a05cad4	17	* Copyright (c) 2003-2004 Axon Digital Design B.V., The Netherlands.
igorsk	0:b56b6a05cad4	18	* All rights reserved.
igorsk	0:b56b6a05cad4	19	*
igorsk	0:b56b6a05cad4	20	* Redistribution and use in source and binary forms, with or without modification,
igorsk	0:b56b6a05cad4	21	* are permitted provided that the following conditions are met:
igorsk	0:b56b6a05cad4	22	*
igorsk	0:b56b6a05cad4	23	* 1. Redistributions of source code must retain the above copyright notice,
igorsk	0:b56b6a05cad4	24	* this list of conditions and the following disclaimer.
igorsk	0:b56b6a05cad4	25	* 2. Redistributions in binary form must reproduce the above copyright notice,
igorsk	0:b56b6a05cad4	26	* this list of conditions and the following disclaimer in the documentation
igorsk	0:b56b6a05cad4	27	* and/or other materials provided with the distribution.
igorsk	0:b56b6a05cad4	28	* 3. The name of the author may not be used to endorse or promote products
igorsk	0:b56b6a05cad4	29	* derived from this software without specific prior written permission.
igorsk	0:b56b6a05cad4	30	*
igorsk	0:b56b6a05cad4	31	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
igorsk	0:b56b6a05cad4	32	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
igorsk	0:b56b6a05cad4	33	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
igorsk	0:b56b6a05cad4	34	* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
igorsk	0:b56b6a05cad4	35	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
igorsk	0:b56b6a05cad4	36	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
igorsk	0:b56b6a05cad4	37	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
igorsk	0:b56b6a05cad4	38	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
igorsk	0:b56b6a05cad4	39	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
igorsk	0:b56b6a05cad4	40	* OF SUCH DAMAGE.
igorsk	0:b56b6a05cad4	41	*
igorsk	0:b56b6a05cad4	42	* This file is part of the lwIP TCP/IP stack.
igorsk	0:b56b6a05cad4	43	*
igorsk	0:b56b6a05cad4	44	*/
igorsk	0:b56b6a05cad4	45
igorsk	0:b56b6a05cad4	46	#include "lwip/opt.h"
igorsk	0:b56b6a05cad4	47
igorsk	0:b56b6a05cad4	48	#if LWIP_ARP \|\| LWIP_ETHERNET
igorsk	0:b56b6a05cad4	49
igorsk	0:b56b6a05cad4	50	#include "lwip/ip_addr.h"
igorsk	0:b56b6a05cad4	51	#include "lwip/def.h"
igorsk	0:b56b6a05cad4	52	#include "lwip/ip.h"
igorsk	0:b56b6a05cad4	53	#include "lwip/stats.h"
igorsk	0:b56b6a05cad4	54	#include "lwip/snmp.h"
igorsk	0:b56b6a05cad4	55	#include "lwip/dhcp.h"
igorsk	0:b56b6a05cad4	56	#include "lwip/autoip.h"
igorsk	0:b56b6a05cad4	57	#include "netif/etharp.h"
igorsk	0:b56b6a05cad4	58
igorsk	0:b56b6a05cad4	59	#if PPPOE_SUPPORT
igorsk	0:b56b6a05cad4	60	#include "netif/ppp_oe.h"
igorsk	0:b56b6a05cad4	61	#endif /* PPPOE_SUPPORT */
igorsk	0:b56b6a05cad4	62
igorsk	0:b56b6a05cad4	63	#include <string.h>
igorsk	0:b56b6a05cad4	64
igorsk	0:b56b6a05cad4	65	const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}};
igorsk	0:b56b6a05cad4	66	const struct eth_addr ethzero = {{0,0,0,0,0,0}};
igorsk	0:b56b6a05cad4	67
igorsk	0:b56b6a05cad4	68	#if LWIP_ARP /* don't build if not configured for use in lwipopts.h */
igorsk	0:b56b6a05cad4	69
igorsk	0:b56b6a05cad4	70	/** the time an ARP entry stays valid after its last update,
igorsk	0:b56b6a05cad4	71	* for ARP_TMR_INTERVAL = 5000, this is
igorsk	0:b56b6a05cad4	72	* (240 * 5) seconds = 20 minutes.
igorsk	0:b56b6a05cad4	73	*/
igorsk	0:b56b6a05cad4	74	#define ARP_MAXAGE 240
igorsk	0:b56b6a05cad4	75	/** the time an ARP entry stays pending after first request,
igorsk	0:b56b6a05cad4	76	* for ARP_TMR_INTERVAL = 5000, this is
igorsk	0:b56b6a05cad4	77	* (2 * 5) seconds = 10 seconds.
igorsk	0:b56b6a05cad4	78	*
igorsk	0:b56b6a05cad4	79	* @internal Keep this number at least 2, otherwise it might
igorsk	0:b56b6a05cad4	80	* run out instantly if the timeout occurs directly after a request.
igorsk	0:b56b6a05cad4	81	*/
igorsk	0:b56b6a05cad4	82	#define ARP_MAXPENDING 2
igorsk	0:b56b6a05cad4	83
igorsk	0:b56b6a05cad4	84	#define HWTYPE_ETHERNET 1
igorsk	0:b56b6a05cad4	85
igorsk	0:b56b6a05cad4	86	enum etharp_state {
igorsk	0:b56b6a05cad4	87	ETHARP_STATE_EMPTY = 0,
igorsk	0:b56b6a05cad4	88	ETHARP_STATE_PENDING,
igorsk	0:b56b6a05cad4	89	ETHARP_STATE_STABLE
igorsk	0:b56b6a05cad4	90	};
igorsk	0:b56b6a05cad4	91
igorsk	0:b56b6a05cad4	92	struct etharp_entry {
igorsk	0:b56b6a05cad4	93	#if ARP_QUEUEING
igorsk	0:b56b6a05cad4	94	/** Pointer to queue of pending outgoing packets on this ARP entry. */
igorsk	0:b56b6a05cad4	95	struct etharp_q_entry *q;
igorsk	0:b56b6a05cad4	96	#endif /* ARP_QUEUEING */
igorsk	0:b56b6a05cad4	97	ip_addr_t ipaddr;
igorsk	0:b56b6a05cad4	98	struct eth_addr ethaddr;
igorsk	0:b56b6a05cad4	99	#if LWIP_SNMP
igorsk	0:b56b6a05cad4	100	struct netif *netif;
igorsk	0:b56b6a05cad4	101	#endif /* LWIP_SNMP */
igorsk	0:b56b6a05cad4	102	u8_t state;
igorsk	0:b56b6a05cad4	103	u8_t ctime;
igorsk	0:b56b6a05cad4	104	#if ETHARP_SUPPORT_STATIC_ENTRIES
igorsk	0:b56b6a05cad4	105	u8_t static_entry;
igorsk	0:b56b6a05cad4	106	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
igorsk	0:b56b6a05cad4	107	};
igorsk	0:b56b6a05cad4	108
igorsk	0:b56b6a05cad4	109	static struct etharp_entry arp_table[ARP_TABLE_SIZE];
igorsk	0:b56b6a05cad4	110
igorsk	0:b56b6a05cad4	111	#if !LWIP_NETIF_HWADDRHINT
igorsk	0:b56b6a05cad4	112	static u8_t etharp_cached_entry;
igorsk	0:b56b6a05cad4	113	#endif /* !LWIP_NETIF_HWADDRHINT */
igorsk	0:b56b6a05cad4	114
igorsk	0:b56b6a05cad4	115	/** Try hard to create a new entry - we want the IP address to appear in
igorsk	0:b56b6a05cad4	116	the cache (even if this means removing an active entry or so). */
igorsk	0:b56b6a05cad4	117	#define ETHARP_FLAG_TRY_HARD 1
igorsk	0:b56b6a05cad4	118	#define ETHARP_FLAG_FIND_ONLY 2
igorsk	0:b56b6a05cad4	119	#define ETHARP_FLAG_STATIC_ENTRY 4
igorsk	0:b56b6a05cad4	120
igorsk	0:b56b6a05cad4	121	#if LWIP_NETIF_HWADDRHINT
igorsk	0:b56b6a05cad4	122	#define ETHARP_SET_HINT(netif, hint) if (((netif) != NULL) && ((netif)->addr_hint != NULL)) \
igorsk	0:b56b6a05cad4	123	*((netif)->addr_hint) = (hint);
igorsk	0:b56b6a05cad4	124	#else /* LWIP_NETIF_HWADDRHINT */
igorsk	0:b56b6a05cad4	125	#define ETHARP_SET_HINT(netif, hint) (etharp_cached_entry = (hint))
igorsk	0:b56b6a05cad4	126	#endif /* LWIP_NETIF_HWADDRHINT */
igorsk	0:b56b6a05cad4	127
igorsk	0:b56b6a05cad4	128	static err_t update_arp_entry(struct netif netif, ip_addr_t ipaddr, struct eth_addr *ethaddr, u8_t flags);
igorsk	0:b56b6a05cad4	129
igorsk	0:b56b6a05cad4	130
igorsk	0:b56b6a05cad4	131	/* Some checks, instead of etharp_init(): */
igorsk	0:b56b6a05cad4	132	#if (LWIP_ARP && (ARP_TABLE_SIZE > 0x7f))
igorsk	0:b56b6a05cad4	133	#error "ARP_TABLE_SIZE must fit in an s8_t, you have to reduce it in your lwipopts.h"
igorsk	0:b56b6a05cad4	134	#endif
igorsk	0:b56b6a05cad4	135
igorsk	0:b56b6a05cad4	136
igorsk	0:b56b6a05cad4	137	#if ARP_QUEUEING
igorsk	0:b56b6a05cad4	138	/**
igorsk	0:b56b6a05cad4	139	* Free a complete queue of etharp entries
igorsk	0:b56b6a05cad4	140	*
igorsk	0:b56b6a05cad4	141	* @param q a qeueue of etharp_q_entry's to free
igorsk	0:b56b6a05cad4	142	*/
igorsk	0:b56b6a05cad4	143	static void
igorsk	0:b56b6a05cad4	144	free_etharp_q(struct etharp_q_entry *q)
igorsk	0:b56b6a05cad4	145	{
igorsk	0:b56b6a05cad4	146	struct etharp_q_entry *r;
igorsk	0:b56b6a05cad4	147	LWIP_ASSERT("q != NULL", q != NULL);
igorsk	0:b56b6a05cad4	148	LWIP_ASSERT("q->p != NULL", q->p != NULL);
igorsk	0:b56b6a05cad4	149	while (q) {
igorsk	0:b56b6a05cad4	150	r = q;
igorsk	0:b56b6a05cad4	151	q = q->next;
igorsk	0:b56b6a05cad4	152	LWIP_ASSERT("r->p != NULL", (r->p != NULL));
igorsk	0:b56b6a05cad4	153	pbuf_free(r->p);
igorsk	0:b56b6a05cad4	154	memp_free(MEMP_ARP_QUEUE, r);
igorsk	0:b56b6a05cad4	155	}
igorsk	0:b56b6a05cad4	156	}
igorsk	0:b56b6a05cad4	157	#endif /* ARP_QUEUEING */
igorsk	0:b56b6a05cad4	158
igorsk	0:b56b6a05cad4	159	/** Clean up ARP table entries */
igorsk	0:b56b6a05cad4	160	static void
igorsk	0:b56b6a05cad4	161	free_entry(int i)
igorsk	0:b56b6a05cad4	162	{
igorsk	0:b56b6a05cad4	163	/* remove from SNMP ARP index tree */
igorsk	0:b56b6a05cad4	164	snmp_delete_arpidx_tree(arp_table[i].netif, &arp_table[i].ipaddr);
igorsk	0:b56b6a05cad4	165	#if ARP_QUEUEING
igorsk	0:b56b6a05cad4	166	/* and empty packet queue */
igorsk	0:b56b6a05cad4	167	if (arp_table[i].q != NULL) {
igorsk	0:b56b6a05cad4	168	/* remove all queued packets */
igorsk	0:b56b6a05cad4	169	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: freeing entry %"U16_F", packet queue %p.\n", (u16_t)i, (void *)(arp_table[i].q)));
igorsk	0:b56b6a05cad4	170	free_etharp_q(arp_table[i].q);
igorsk	0:b56b6a05cad4	171	arp_table[i].q = NULL;
igorsk	0:b56b6a05cad4	172	}
igorsk	0:b56b6a05cad4	173	#endif /* ARP_QUEUEING */
igorsk	0:b56b6a05cad4	174	/* recycle entry for re-use */
igorsk	0:b56b6a05cad4	175	arp_table[i].state = ETHARP_STATE_EMPTY;
igorsk	0:b56b6a05cad4	176	#if ETHARP_SUPPORT_STATIC_ENTRIES
igorsk	0:b56b6a05cad4	177	arp_table[i].static_entry = 0;
igorsk	0:b56b6a05cad4	178	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
igorsk	0:b56b6a05cad4	179	#ifdef LWIP_DEBUG
igorsk	0:b56b6a05cad4	180	/* for debugging, clean out the complete entry */
igorsk	0:b56b6a05cad4	181	arp_table[i].ctime = 0;
igorsk	0:b56b6a05cad4	182	#if LWIP_SNMP
igorsk	0:b56b6a05cad4	183	arp_table[i].netif = NULL;
igorsk	0:b56b6a05cad4	184	#endif /* LWIP_SNMP */
igorsk	0:b56b6a05cad4	185	ip_addr_set_zero(&arp_table[i].ipaddr);
igorsk	0:b56b6a05cad4	186	arp_table[i].ethaddr = ethzero;
igorsk	0:b56b6a05cad4	187	#endif /* LWIP_DEBUG */
igorsk	0:b56b6a05cad4	188	}
igorsk	0:b56b6a05cad4	189
igorsk	0:b56b6a05cad4	190	/**
igorsk	0:b56b6a05cad4	191	* Clears expired entries in the ARP table.
igorsk	0:b56b6a05cad4	192	*
igorsk	0:b56b6a05cad4	193	* This function should be called every ETHARP_TMR_INTERVAL milliseconds (5 seconds),
igorsk	0:b56b6a05cad4	194	* in order to expire entries in the ARP table.
igorsk	0:b56b6a05cad4	195	*/
igorsk	0:b56b6a05cad4	196	void
igorsk	0:b56b6a05cad4	197	etharp_tmr(void)
igorsk	0:b56b6a05cad4	198	{
igorsk	0:b56b6a05cad4	199	u8_t i;
igorsk	0:b56b6a05cad4	200
igorsk	0:b56b6a05cad4	201	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer\n"));
igorsk	0:b56b6a05cad4	202	/* remove expired entries from the ARP table */
igorsk	0:b56b6a05cad4	203	for (i = 0; i < ARP_TABLE_SIZE; ++i) {
igorsk	0:b56b6a05cad4	204	u8_t state = arp_table[i].state;
igorsk	0:b56b6a05cad4	205	if (state != ETHARP_STATE_EMPTY
igorsk	0:b56b6a05cad4	206	#if ETHARP_SUPPORT_STATIC_ENTRIES
igorsk	0:b56b6a05cad4	207	&& (arp_table[i].static_entry == 0)
igorsk	0:b56b6a05cad4	208	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
igorsk	0:b56b6a05cad4	209	) {
igorsk	0:b56b6a05cad4	210	arp_table[i].ctime++;
igorsk	0:b56b6a05cad4	211	if ((arp_table[i].ctime >= ARP_MAXAGE) \|\|
igorsk	0:b56b6a05cad4	212	((arp_table[i].state == ETHARP_STATE_PENDING) &&
igorsk	0:b56b6a05cad4	213	(arp_table[i].ctime >= ARP_MAXPENDING))) {
igorsk	0:b56b6a05cad4	214	/* pending or stable entry has become old! */
igorsk	0:b56b6a05cad4	215	LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: expired %s entry %"U16_F".\n",
igorsk	0:b56b6a05cad4	216	arp_table[i].state == ETHARP_STATE_STABLE ? "stable" : "pending", (u16_t)i));
igorsk	0:b56b6a05cad4	217	/* clean up entries that have just been expired */
igorsk	0:b56b6a05cad4	218	free_entry(i);
igorsk	0:b56b6a05cad4	219	}
igorsk	0:b56b6a05cad4	220	#if ARP_QUEUEING
igorsk	0:b56b6a05cad4	221	/* still pending entry? (not expired) */
igorsk	0:b56b6a05cad4	222	if (arp_table[i].state == ETHARP_STATE_PENDING) {
igorsk	0:b56b6a05cad4	223	/* resend an ARP query here? */
igorsk	0:b56b6a05cad4	224	}
igorsk	0:b56b6a05cad4	225	#endif /* ARP_QUEUEING */
igorsk	0:b56b6a05cad4	226	}
igorsk	0:b56b6a05cad4	227	}
igorsk	0:b56b6a05cad4	228	}
igorsk	0:b56b6a05cad4	229
igorsk	0:b56b6a05cad4	230	/**
igorsk	0:b56b6a05cad4	231	* Search the ARP table for a matching or new entry.
igorsk	0:b56b6a05cad4	232	*
igorsk	0:b56b6a05cad4	233	* If an IP address is given, return a pending or stable ARP entry that matches
igorsk	0:b56b6a05cad4	234	* the address. If no match is found, create a new entry with this address set,
igorsk	0:b56b6a05cad4	235	* but in state ETHARP_EMPTY. The caller must check and possibly change the
igorsk	0:b56b6a05cad4	236	* state of the returned entry.
igorsk	0:b56b6a05cad4	237	*
igorsk	0:b56b6a05cad4	238	* If ipaddr is NULL, return a initialized new entry in state ETHARP_EMPTY.
igorsk	0:b56b6a05cad4	239	*
igorsk	0:b56b6a05cad4	240	* In all cases, attempt to create new entries from an empty entry. If no
igorsk	0:b56b6a05cad4	241	* empty entries are available and ETHARP_FLAG_TRY_HARD flag is set, recycle
igorsk	0:b56b6a05cad4	242	* old entries. Heuristic choose the least important entry for recycling.
igorsk	0:b56b6a05cad4	243	*
igorsk	0:b56b6a05cad4	244	* @param ipaddr IP address to find in ARP cache, or to add if not found.
igorsk	0:b56b6a05cad4	245	* @param flags @see definition of ETHARP_FLAG_*
igorsk	0:b56b6a05cad4	246	* @param netif netif related to this address (used for NETIF_HWADDRHINT)
igorsk	0:b56b6a05cad4	247	*
igorsk	0:b56b6a05cad4	248	* @return The ARP entry index that matched or is created, ERR_MEM if no
igorsk	0:b56b6a05cad4	249	* entry is found or could be recycled.
igorsk	0:b56b6a05cad4	250	*/
igorsk	0:b56b6a05cad4	251	static s8_t
igorsk	0:b56b6a05cad4	252	find_entry(ip_addr_t *ipaddr, u8_t flags)
igorsk	0:b56b6a05cad4	253	{
igorsk	0:b56b6a05cad4	254	s8_t old_pending = ARP_TABLE_SIZE, old_stable = ARP_TABLE_SIZE;
igorsk	0:b56b6a05cad4	255	s8_t empty = ARP_TABLE_SIZE;
igorsk	0:b56b6a05cad4	256	u8_t i = 0, age_pending = 0, age_stable = 0;
igorsk	0:b56b6a05cad4	257	#if ARP_QUEUEING
igorsk	0:b56b6a05cad4	258	/* oldest entry with packets on queue */
igorsk	0:b56b6a05cad4	259	s8_t old_queue = ARP_TABLE_SIZE;
igorsk	0:b56b6a05cad4	260	/* its age */
igorsk	0:b56b6a05cad4	261	u8_t age_queue = 0;
igorsk	0:b56b6a05cad4	262	#endif /* ARP_QUEUEING */
igorsk	0:b56b6a05cad4	263
igorsk	0:b56b6a05cad4	264	/**
igorsk	0:b56b6a05cad4	265	* a) do a search through the cache, remember candidates
igorsk	0:b56b6a05cad4	266	* b) select candidate entry
igorsk	0:b56b6a05cad4	267	* c) create new entry
igorsk	0:b56b6a05cad4	268	*/
igorsk	0:b56b6a05cad4	269
igorsk	0:b56b6a05cad4	270	/* a) in a single search sweep, do all of this
igorsk	0:b56b6a05cad4	271	* 1) remember the first empty entry (if any)
igorsk	0:b56b6a05cad4	272	* 2) remember the oldest stable entry (if any)
igorsk	0:b56b6a05cad4	273	* 3) remember the oldest pending entry without queued packets (if any)
igorsk	0:b56b6a05cad4	274	* 4) remember the oldest pending entry with queued packets (if any)
igorsk	0:b56b6a05cad4	275	* 5) search for a matching IP entry, either pending or stable
igorsk	0:b56b6a05cad4	276	* until 5 matches, or all entries are searched for.
igorsk	0:b56b6a05cad4	277	*/
igorsk	0:b56b6a05cad4	278
igorsk	0:b56b6a05cad4	279	for (i = 0; i < ARP_TABLE_SIZE; ++i) {
igorsk	0:b56b6a05cad4	280	u8_t state = arp_table[i].state;
igorsk	0:b56b6a05cad4	281	/* no empty entry found yet and now we do find one? */
igorsk	0:b56b6a05cad4	282	if ((empty == ARP_TABLE_SIZE) && (state == ETHARP_STATE_EMPTY)) {
igorsk	0:b56b6a05cad4	283	LWIP_DEBUGF(ETHARP_DEBUG, ("find_entry: found empty entry %"U16_F"\n", (u16_t)i));
igorsk	0:b56b6a05cad4	284	/* remember first empty entry */
igorsk	0:b56b6a05cad4	285	empty = i;
igorsk	0:b56b6a05cad4	286	} else if (state != ETHARP_STATE_EMPTY) {
igorsk	0:b56b6a05cad4	287	LWIP_ASSERT("state == ETHARP_STATE_PENDING \|\| state == ETHARP_STATE_STABLE",
igorsk	0:b56b6a05cad4	288	state == ETHARP_STATE_PENDING \|\| state == ETHARP_STATE_STABLE);
igorsk	0:b56b6a05cad4	289	/* if given, does IP address match IP address in ARP entry? */
igorsk	0:b56b6a05cad4	290	if (ipaddr && ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
igorsk	0:b56b6a05cad4	291	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: found matching entry %"U16_F"\n", (u16_t)i));
igorsk	0:b56b6a05cad4	292	/* found exact IP address match, simply bail out */
igorsk	0:b56b6a05cad4	293	return i;
igorsk	0:b56b6a05cad4	294	}
igorsk	0:b56b6a05cad4	295	/* pending entry? */
igorsk	0:b56b6a05cad4	296	if (state == ETHARP_STATE_PENDING) {
igorsk	0:b56b6a05cad4	297	/* pending with queued packets? */
igorsk	0:b56b6a05cad4	298	#if ARP_QUEUEING
igorsk	0:b56b6a05cad4	299	if (arp_table[i].q != NULL) {
igorsk	0:b56b6a05cad4	300	if (arp_table[i].ctime >= age_queue) {
igorsk	0:b56b6a05cad4	301	old_queue = i;
igorsk	0:b56b6a05cad4	302	age_queue = arp_table[i].ctime;
igorsk	0:b56b6a05cad4	303	}
igorsk	0:b56b6a05cad4	304	} else
igorsk	0:b56b6a05cad4	305	#endif /* ARP_QUEUEING */
igorsk	0:b56b6a05cad4	306	/* pending without queued packets? */
igorsk	0:b56b6a05cad4	307	{
igorsk	0:b56b6a05cad4	308	if (arp_table[i].ctime >= age_pending) {
igorsk	0:b56b6a05cad4	309	old_pending = i;
igorsk	0:b56b6a05cad4	310	age_pending = arp_table[i].ctime;
igorsk	0:b56b6a05cad4	311	}
igorsk	0:b56b6a05cad4	312	}
igorsk	0:b56b6a05cad4	313	/* stable entry? */
igorsk	0:b56b6a05cad4	314	} else if (state == ETHARP_STATE_STABLE) {
igorsk	0:b56b6a05cad4	315	#if ETHARP_SUPPORT_STATIC_ENTRIES
igorsk	0:b56b6a05cad4	316	/* don't record old_stable for static entries since they never expire */
igorsk	0:b56b6a05cad4	317	if (arp_table[i].static_entry == 0)
igorsk	0:b56b6a05cad4	318	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
igorsk	0:b56b6a05cad4	319	{
igorsk	0:b56b6a05cad4	320	/* remember entry with oldest stable entry in oldest, its age in maxtime */
igorsk	0:b56b6a05cad4	321	if (arp_table[i].ctime >= age_stable) {
igorsk	0:b56b6a05cad4	322	old_stable = i;
igorsk	0:b56b6a05cad4	323	age_stable = arp_table[i].ctime;
igorsk	0:b56b6a05cad4	324	}
igorsk	0:b56b6a05cad4	325	}
igorsk	0:b56b6a05cad4	326	}
igorsk	0:b56b6a05cad4	327	}
igorsk	0:b56b6a05cad4	328	}
igorsk	0:b56b6a05cad4	329	/* { we have no match } => try to create a new entry */
igorsk	0:b56b6a05cad4	330
igorsk	0:b56b6a05cad4	331	/* don't create new entry, only search? */
igorsk	0:b56b6a05cad4	332	if (((flags & ETHARP_FLAG_FIND_ONLY) != 0) \|\|
igorsk	0:b56b6a05cad4	333	/* or no empty entry found and not allowed to recycle? */
igorsk	0:b56b6a05cad4	334	((empty == ARP_TABLE_SIZE) && ((flags & ETHARP_FLAG_TRY_HARD) == 0))) {
igorsk	0:b56b6a05cad4	335	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: no empty entry found and not allowed to recycle\n"));
igorsk	0:b56b6a05cad4	336	return (s8_t)ERR_MEM;
igorsk	0:b56b6a05cad4	337	}
igorsk	0:b56b6a05cad4	338
igorsk	0:b56b6a05cad4	339	/* b) choose the least destructive entry to recycle:
igorsk	0:b56b6a05cad4	340	* 1) empty entry
igorsk	0:b56b6a05cad4	341	* 2) oldest stable entry
igorsk	0:b56b6a05cad4	342	* 3) oldest pending entry without queued packets
igorsk	0:b56b6a05cad4	343	* 4) oldest pending entry with queued packets
igorsk	0:b56b6a05cad4	344	*
igorsk	0:b56b6a05cad4	345	* { ETHARP_FLAG_TRY_HARD is set at this point }
igorsk	0:b56b6a05cad4	346	*/
igorsk	0:b56b6a05cad4	347
igorsk	0:b56b6a05cad4	348	/* 1) empty entry available? */
igorsk	0:b56b6a05cad4	349	if (empty < ARP_TABLE_SIZE) {
igorsk	0:b56b6a05cad4	350	i = empty;
igorsk	0:b56b6a05cad4	351	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting empty entry %"U16_F"\n", (u16_t)i));
igorsk	0:b56b6a05cad4	352	} else {
igorsk	0:b56b6a05cad4	353	/* 2) found recyclable stable entry? */
igorsk	0:b56b6a05cad4	354	if (old_stable < ARP_TABLE_SIZE) {
igorsk	0:b56b6a05cad4	355	/* recycle oldest stable*/
igorsk	0:b56b6a05cad4	356	i = old_stable;
igorsk	0:b56b6a05cad4	357	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest stable entry %"U16_F"\n", (u16_t)i));
igorsk	0:b56b6a05cad4	358	#if ARP_QUEUEING
igorsk	0:b56b6a05cad4	359	/* no queued packets should exist on stable entries */
igorsk	0:b56b6a05cad4	360	LWIP_ASSERT("arp_table[i].q == NULL", arp_table[i].q == NULL);
igorsk	0:b56b6a05cad4	361	#endif /* ARP_QUEUEING */
igorsk	0:b56b6a05cad4	362	/* 3) found recyclable pending entry without queued packets? */
igorsk	0:b56b6a05cad4	363	} else if (old_pending < ARP_TABLE_SIZE) {
igorsk	0:b56b6a05cad4	364	/* recycle oldest pending */
igorsk	0:b56b6a05cad4	365	i = old_pending;
igorsk	0:b56b6a05cad4	366	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: selecting oldest pending entry %"U16_F" (without queue)\n", (u16_t)i));
igorsk	0:b56b6a05cad4	367	#if ARP_QUEUEING
igorsk	0:b56b6a05cad4	368	/* 4) found recyclable pending entry with queued packets? */
igorsk	0:b56b6a05cad4	369	} else if (old_queue < ARP_TABLE_SIZE) {
igorsk	0:b56b6a05cad4	370	/* recycle oldest pending (queued packets are free in free_entry) */
igorsk	0:b56b6a05cad4	371	i = old_queue;
igorsk	0:b56b6a05cad4	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)));
igorsk	0:b56b6a05cad4	373	#endif /* ARP_QUEUEING */
igorsk	0:b56b6a05cad4	374	/* no empty or recyclable entries found */
igorsk	0:b56b6a05cad4	375	} else {
igorsk	0:b56b6a05cad4	376	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("find_entry: no empty or recyclable entries found\n"));
igorsk	0:b56b6a05cad4	377	return (s8_t)ERR_MEM;
igorsk	0:b56b6a05cad4	378	}
igorsk	0:b56b6a05cad4	379
igorsk	0:b56b6a05cad4	380	/* { empty or recyclable entry found } */
igorsk	0:b56b6a05cad4	381	LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
igorsk	0:b56b6a05cad4	382	free_entry(i);
igorsk	0:b56b6a05cad4	383	}
igorsk	0:b56b6a05cad4	384
igorsk	0:b56b6a05cad4	385	LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
igorsk	0:b56b6a05cad4	386	LWIP_ASSERT("arp_table[i].state == ETHARP_STATE_EMPTY",
igorsk	0:b56b6a05cad4	387	arp_table[i].state == ETHARP_STATE_EMPTY);
igorsk	0:b56b6a05cad4	388
igorsk	0:b56b6a05cad4	389	/* IP address given? */
igorsk	0:b56b6a05cad4	390	if (ipaddr != NULL) {
igorsk	0:b56b6a05cad4	391	/* set IP address */
igorsk	0:b56b6a05cad4	392	ip_addr_copy(arp_table[i].ipaddr, *ipaddr);
igorsk	0:b56b6a05cad4	393	}
igorsk	0:b56b6a05cad4	394	arp_table[i].ctime = 0;
igorsk	0:b56b6a05cad4	395	#if ETHARP_SUPPORT_STATIC_ENTRIES
igorsk	0:b56b6a05cad4	396	arp_table[i].static_entry = 0;
igorsk	0:b56b6a05cad4	397	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
igorsk	0:b56b6a05cad4	398	return (err_t)i;
igorsk	0:b56b6a05cad4	399	}
igorsk	0:b56b6a05cad4	400
igorsk	0:b56b6a05cad4	401	/**
igorsk	0:b56b6a05cad4	402	* Send an IP packet on the network using netif->linkoutput
igorsk	0:b56b6a05cad4	403	* The ethernet header is filled in before sending.
igorsk	0:b56b6a05cad4	404	*
igorsk	0:b56b6a05cad4	405	* @params netif the lwIP network interface on which to send the packet
igorsk	0:b56b6a05cad4	406	* @params p the packet to send, p->payload pointing to the (uninitialized) ethernet header
igorsk	0:b56b6a05cad4	407	* @params src the source MAC address to be copied into the ethernet header
igorsk	0:b56b6a05cad4	408	* @params dst the destination MAC address to be copied into the ethernet header
igorsk	0:b56b6a05cad4	409	* @return ERR_OK if the packet was sent, any other err_t on failure
igorsk	0:b56b6a05cad4	410	*/
igorsk	0:b56b6a05cad4	411	static err_t
igorsk	0:b56b6a05cad4	412	etharp_send_ip(struct netif netif, struct pbuf p, struct eth_addr src, struct eth_addr dst)
igorsk	0:b56b6a05cad4	413	{
igorsk	0:b56b6a05cad4	414	struct eth_hdr ethhdr = (struct eth_hdr )p->payload;
igorsk	0:b56b6a05cad4	415
igorsk	0:b56b6a05cad4	416	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
igorsk	0:b56b6a05cad4	417	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
igorsk	0:b56b6a05cad4	418	ETHADDR32_COPY(&ethhdr->dest, dst);
igorsk	0:b56b6a05cad4	419	ETHADDR16_COPY(&ethhdr->src, src);
igorsk	0:b56b6a05cad4	420	ethhdr->type = PP_HTONS(ETHTYPE_IP);
igorsk	0:b56b6a05cad4	421	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_send_ip: sending packet %p\n", (void *)p));
igorsk	0:b56b6a05cad4	422	/* send the packet */
igorsk	0:b56b6a05cad4	423	return netif->linkoutput(netif, p);
igorsk	0:b56b6a05cad4	424	}
igorsk	0:b56b6a05cad4	425
igorsk	0:b56b6a05cad4	426	/**
igorsk	0:b56b6a05cad4	427	* Update (or insert) a IP/MAC address pair in the ARP cache.
igorsk	0:b56b6a05cad4	428	*
igorsk	0:b56b6a05cad4	429	* If a pending entry is resolved, any queued packets will be sent
igorsk	0:b56b6a05cad4	430	* at this point.
igorsk	0:b56b6a05cad4	431	*
igorsk	0:b56b6a05cad4	432	* @param netif netif related to this entry (used for NETIF_ADDRHINT)
igorsk	0:b56b6a05cad4	433	* @param ipaddr IP address of the inserted ARP entry.
igorsk	0:b56b6a05cad4	434	* @param ethaddr Ethernet address of the inserted ARP entry.
igorsk	0:b56b6a05cad4	435	* @param flags @see definition of ETHARP_FLAG_*
igorsk	0:b56b6a05cad4	436	*
igorsk	0:b56b6a05cad4	437	* @return
igorsk	0:b56b6a05cad4	438	* - ERR_OK Succesfully updated ARP cache.
igorsk	0:b56b6a05cad4	439	* - ERR_MEM If we could not add a new ARP entry when ETHARP_FLAG_TRY_HARD was set.
igorsk	0:b56b6a05cad4	440	* - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
igorsk	0:b56b6a05cad4	441	*
igorsk	0:b56b6a05cad4	442	* @see pbuf_free()
igorsk	0:b56b6a05cad4	443	*/
igorsk	0:b56b6a05cad4	444	static err_t
igorsk	0:b56b6a05cad4	445	update_arp_entry(struct netif netif, ip_addr_t ipaddr, struct eth_addr *ethaddr, u8_t flags)
igorsk	0:b56b6a05cad4	446	{
igorsk	0:b56b6a05cad4	447	s8_t i;
igorsk	0:b56b6a05cad4	448	LWIP_ASSERT("netif->hwaddr_len == ETHARP_HWADDR_LEN", netif->hwaddr_len == ETHARP_HWADDR_LEN);
igorsk	0:b56b6a05cad4	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",
igorsk	0:b56b6a05cad4	450	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
igorsk	0:b56b6a05cad4	451	ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
igorsk	0:b56b6a05cad4	452	ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
igorsk	0:b56b6a05cad4	453	/* non-unicast address? */
igorsk	0:b56b6a05cad4	454	if (ip_addr_isany(ipaddr) \|\|
igorsk	0:b56b6a05cad4	455	ip_addr_isbroadcast(ipaddr, netif) \|\|
igorsk	0:b56b6a05cad4	456	ip_addr_ismulticast(ipaddr)) {
igorsk	0:b56b6a05cad4	457	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: will not add non-unicast IP address to ARP cache\n"));
igorsk	0:b56b6a05cad4	458	return ERR_ARG;
igorsk	0:b56b6a05cad4	459	}
igorsk	0:b56b6a05cad4	460	/* find or create ARP entry */
igorsk	0:b56b6a05cad4	461	i = find_entry(ipaddr, flags);
igorsk	0:b56b6a05cad4	462	/* bail out if no entry could be found */
igorsk	0:b56b6a05cad4	463	if (i < 0) {
igorsk	0:b56b6a05cad4	464	return (err_t)i;
igorsk	0:b56b6a05cad4	465	}
igorsk	0:b56b6a05cad4	466
igorsk	0:b56b6a05cad4	467	#if ETHARP_SUPPORT_STATIC_ENTRIES
igorsk	0:b56b6a05cad4	468	if (flags & ETHARP_FLAG_STATIC_ENTRY) {
igorsk	0:b56b6a05cad4	469	/* record static type */
igorsk	0:b56b6a05cad4	470	arp_table[i].static_entry = 1;
igorsk	0:b56b6a05cad4	471	}
igorsk	0:b56b6a05cad4	472	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
igorsk	0:b56b6a05cad4	473
igorsk	0:b56b6a05cad4	474	/* mark it stable */
igorsk	0:b56b6a05cad4	475	arp_table[i].state = ETHARP_STATE_STABLE;
igorsk	0:b56b6a05cad4	476
igorsk	0:b56b6a05cad4	477	#if LWIP_SNMP
igorsk	0:b56b6a05cad4	478	/* record network interface */
igorsk	0:b56b6a05cad4	479	arp_table[i].netif = netif;
igorsk	0:b56b6a05cad4	480	#endif /* LWIP_SNMP */
igorsk	0:b56b6a05cad4	481	/* insert in SNMP ARP index tree */
igorsk	0:b56b6a05cad4	482	snmp_insert_arpidx_tree(netif, &arp_table[i].ipaddr);
igorsk	0:b56b6a05cad4	483
igorsk	0:b56b6a05cad4	484	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("update_arp_entry: updating stable entry %"S16_F"\n", (s16_t)i));
igorsk	0:b56b6a05cad4	485	/* update address */
igorsk	0:b56b6a05cad4	486	ETHADDR32_COPY(&arp_table[i].ethaddr, ethaddr);
igorsk	0:b56b6a05cad4	487	/* reset time stamp */
igorsk	0:b56b6a05cad4	488	arp_table[i].ctime = 0;
igorsk	0:b56b6a05cad4	489	#if ARP_QUEUEING
igorsk	0:b56b6a05cad4	490	/* this is where we will send out queued packets! */
igorsk	0:b56b6a05cad4	491	while (arp_table[i].q != NULL) {
igorsk	0:b56b6a05cad4	492	struct pbuf *p;
igorsk	0:b56b6a05cad4	493	/* remember remainder of queue */
igorsk	0:b56b6a05cad4	494	struct etharp_q_entry *q = arp_table[i].q;
igorsk	0:b56b6a05cad4	495	/* pop first item off the queue */
igorsk	0:b56b6a05cad4	496	arp_table[i].q = q->next;
igorsk	0:b56b6a05cad4	497	/* get the packet pointer */
igorsk	0:b56b6a05cad4	498	p = q->p;
igorsk	0:b56b6a05cad4	499	/* now queue entry can be freed */
igorsk	0:b56b6a05cad4	500	memp_free(MEMP_ARP_QUEUE, q);
igorsk	0:b56b6a05cad4	501	/* send the queued IP packet */
igorsk	0:b56b6a05cad4	502	etharp_send_ip(netif, p, (struct eth_addr*)(netif->hwaddr), ethaddr);
igorsk	0:b56b6a05cad4	503	/* free the queued IP packet */
igorsk	0:b56b6a05cad4	504	pbuf_free(p);
igorsk	0:b56b6a05cad4	505	}
igorsk	0:b56b6a05cad4	506	#endif /* ARP_QUEUEING */
igorsk	0:b56b6a05cad4	507	return ERR_OK;
igorsk	0:b56b6a05cad4	508	}
igorsk	0:b56b6a05cad4	509
igorsk	0:b56b6a05cad4	510	#if ETHARP_SUPPORT_STATIC_ENTRIES
igorsk	0:b56b6a05cad4	511	/** Add a new static entry to the ARP table. If an entry exists for the
igorsk	0:b56b6a05cad4	512	* specified IP address, this entry is overwritten.
igorsk	0:b56b6a05cad4	513	* If packets are queued for the specified IP address, they are sent out.
igorsk	0:b56b6a05cad4	514	*
igorsk	0:b56b6a05cad4	515	* @param ipaddr IP address for the new static entry
igorsk	0:b56b6a05cad4	516	* @param ethaddr ethernet address for the new static entry
igorsk	0:b56b6a05cad4	517	* @return @see return values of etharp_add_static_entry
igorsk	0:b56b6a05cad4	518	*/
igorsk	0:b56b6a05cad4	519	err_t
igorsk	0:b56b6a05cad4	520	etharp_add_static_entry(ip_addr_t ipaddr, struct eth_addr ethaddr)
igorsk	0:b56b6a05cad4	521	{
igorsk	0:b56b6a05cad4	522	struct netif *netif;
igorsk	0:b56b6a05cad4	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",
igorsk	0:b56b6a05cad4	524	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
igorsk	0:b56b6a05cad4	525	ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
igorsk	0:b56b6a05cad4	526	ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
igorsk	0:b56b6a05cad4	527
igorsk	0:b56b6a05cad4	528	netif = ip_route(ipaddr);
igorsk	0:b56b6a05cad4	529	if (netif == NULL) {
igorsk	0:b56b6a05cad4	530	return ERR_RTE;
igorsk	0:b56b6a05cad4	531	}
igorsk	0:b56b6a05cad4	532
igorsk	0:b56b6a05cad4	533	return update_arp_entry(netif, ipaddr, ethaddr, ETHARP_FLAG_TRY_HARD \| ETHARP_FLAG_STATIC_ENTRY);
igorsk	0:b56b6a05cad4	534	}
igorsk	0:b56b6a05cad4	535
igorsk	0:b56b6a05cad4	536	/** Remove a static entry from the ARP table previously added with a call to
igorsk	0:b56b6a05cad4	537	* etharp_add_static_entry.
igorsk	0:b56b6a05cad4	538	*
igorsk	0:b56b6a05cad4	539	* @param ipaddr IP address of the static entry to remove
igorsk	0:b56b6a05cad4	540	* @return ERR_OK: entry removed
igorsk	0:b56b6a05cad4	541	* ERR_MEM: entry wasn't found
igorsk	0:b56b6a05cad4	542	* ERR_ARG: entry wasn't a static entry but a dynamic one
igorsk	0:b56b6a05cad4	543	*/
igorsk	0:b56b6a05cad4	544	err_t
igorsk	0:b56b6a05cad4	545	etharp_remove_static_entry(ip_addr_t *ipaddr)
igorsk	0:b56b6a05cad4	546	{
igorsk	0:b56b6a05cad4	547	s8_t i;
igorsk	0:b56b6a05cad4	548	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_remove_static_entry: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
igorsk	0:b56b6a05cad4	549	ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr)));
igorsk	0:b56b6a05cad4	550
igorsk	0:b56b6a05cad4	551	/* find or create ARP entry */
igorsk	0:b56b6a05cad4	552	i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
igorsk	0:b56b6a05cad4	553	/* bail out if no entry could be found */
igorsk	0:b56b6a05cad4	554	if (i < 0) {
igorsk	0:b56b6a05cad4	555	return (err_t)i;
igorsk	0:b56b6a05cad4	556	}
igorsk	0:b56b6a05cad4	557
igorsk	0:b56b6a05cad4	558	if ((arp_table[i].state != ETHARP_STATE_STABLE) \|\|
igorsk	0:b56b6a05cad4	559	(arp_table[i].static_entry == 0)) {
igorsk	0:b56b6a05cad4	560	/* entry wasn't a static entry, cannot remove it */
igorsk	0:b56b6a05cad4	561	return ERR_ARG;
igorsk	0:b56b6a05cad4	562	}
igorsk	0:b56b6a05cad4	563	/* entry found, free it */
igorsk	0:b56b6a05cad4	564	free_entry(i);
igorsk	0:b56b6a05cad4	565	return ERR_OK;
igorsk	0:b56b6a05cad4	566	}
igorsk	0:b56b6a05cad4	567	#endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
igorsk	0:b56b6a05cad4	568
igorsk	0:b56b6a05cad4	569	/**
igorsk	0:b56b6a05cad4	570	* Finds (stable) ethernet/IP address pair from ARP table
igorsk	0:b56b6a05cad4	571	* using interface and IP address index.
igorsk	0:b56b6a05cad4	572	* @note the addresses in the ARP table are in network order!
igorsk	0:b56b6a05cad4	573	*
igorsk	0:b56b6a05cad4	574	* @param netif points to interface index
igorsk	0:b56b6a05cad4	575	* @param ipaddr points to the (network order) IP address index
igorsk	0:b56b6a05cad4	576	* @param eth_ret points to return pointer
igorsk	0:b56b6a05cad4	577	* @param ip_ret points to return pointer
igorsk	0:b56b6a05cad4	578	* @return table index if found, -1 otherwise
igorsk	0:b56b6a05cad4	579	*/
igorsk	0:b56b6a05cad4	580	s8_t
igorsk	0:b56b6a05cad4	581	etharp_find_addr(struct netif netif, ip_addr_t ipaddr,
igorsk	0:b56b6a05cad4	582	struct eth_addr eth_ret, ip_addr_t ip_ret)
igorsk	0:b56b6a05cad4	583	{
igorsk	0:b56b6a05cad4	584	s8_t i;
igorsk	0:b56b6a05cad4	585
igorsk	0:b56b6a05cad4	586	LWIP_ASSERT("eth_ret != NULL && ip_ret != NULL",
igorsk	0:b56b6a05cad4	587	eth_ret != NULL && ip_ret != NULL);
igorsk	0:b56b6a05cad4	588
igorsk	0:b56b6a05cad4	589	LWIP_UNUSED_ARG(netif);
igorsk	0:b56b6a05cad4	590
igorsk	0:b56b6a05cad4	591	i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
igorsk	0:b56b6a05cad4	592	if((i >= 0) && arp_table[i].state == ETHARP_STATE_STABLE) {
igorsk	0:b56b6a05cad4	593	*eth_ret = &arp_table[i].ethaddr;
igorsk	0:b56b6a05cad4	594	*ip_ret = &arp_table[i].ipaddr;
igorsk	0:b56b6a05cad4	595	return i;
igorsk	0:b56b6a05cad4	596	}
igorsk	0:b56b6a05cad4	597	return -1;
igorsk	0:b56b6a05cad4	598	}
igorsk	0:b56b6a05cad4	599
igorsk	0:b56b6a05cad4	600	#if ETHARP_TRUST_IP_MAC
igorsk	0:b56b6a05cad4	601	/**
igorsk	0:b56b6a05cad4	602	* Updates the ARP table using the given IP packet.
igorsk	0:b56b6a05cad4	603	*
igorsk	0:b56b6a05cad4	604	* Uses the incoming IP packet's source address to update the
igorsk	0:b56b6a05cad4	605	* ARP cache for the local network. The function does not alter
igorsk	0:b56b6a05cad4	606	* or free the packet. This function must be called before the
igorsk	0:b56b6a05cad4	607	* packet p is passed to the IP layer.
igorsk	0:b56b6a05cad4	608	*
igorsk	0:b56b6a05cad4	609	* @param netif The lwIP network interface on which the IP packet pbuf arrived.
igorsk	0:b56b6a05cad4	610	* @param p The IP packet that arrived on netif.
igorsk	0:b56b6a05cad4	611	*
igorsk	0:b56b6a05cad4	612	* @return NULL
igorsk	0:b56b6a05cad4	613	*
igorsk	0:b56b6a05cad4	614	* @see pbuf_free()
igorsk	0:b56b6a05cad4	615	*/
igorsk	0:b56b6a05cad4	616	static void
igorsk	0:b56b6a05cad4	617	etharp_ip_input(struct netif netif, struct pbuf p)
igorsk	0:b56b6a05cad4	618	{
igorsk	0:b56b6a05cad4	619	struct eth_hdr *ethhdr;
igorsk	0:b56b6a05cad4	620	struct ip_hdr *iphdr;
igorsk	0:b56b6a05cad4	621	ip_addr_t iphdr_src;
igorsk	0:b56b6a05cad4	622	LWIP_ERROR("netif != NULL", (netif != NULL), return;);
igorsk	0:b56b6a05cad4	623
igorsk	0:b56b6a05cad4	624	/* Only insert an entry if the source IP address of the
igorsk	0:b56b6a05cad4	625	incoming IP packet comes from a host on the local network. */
igorsk	0:b56b6a05cad4	626	ethhdr = (struct eth_hdr *)p->payload;
igorsk	0:b56b6a05cad4	627	iphdr = (struct ip_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
igorsk	0:b56b6a05cad4	628	#if ETHARP_SUPPORT_VLAN
igorsk	0:b56b6a05cad4	629	if (ethhdr->type == ETHTYPE_VLAN) {
igorsk	0:b56b6a05cad4	630	iphdr = (struct ip_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
igorsk	0:b56b6a05cad4	631	}
igorsk	0:b56b6a05cad4	632	#endif /* ETHARP_SUPPORT_VLAN */
igorsk	0:b56b6a05cad4	633
igorsk	0:b56b6a05cad4	634	ip_addr_copy(iphdr_src, iphdr->src);
igorsk	0:b56b6a05cad4	635
igorsk	0:b56b6a05cad4	636	/* source is not on the local network? */
igorsk	0:b56b6a05cad4	637	if (!ip_addr_netcmp(&iphdr_src, &(netif->ip_addr), &(netif->netmask))) {
igorsk	0:b56b6a05cad4	638	/* do nothing */
igorsk	0:b56b6a05cad4	639	return;
igorsk	0:b56b6a05cad4	640	}
igorsk	0:b56b6a05cad4	641
igorsk	0:b56b6a05cad4	642	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_ip_input: updating ETHARP table.\n"));
igorsk	0:b56b6a05cad4	643	/* update the source IP address in the cache, if present */
igorsk	0:b56b6a05cad4	644	/* @todo We could use ETHARP_FLAG_TRY_HARD if we think we are going to talk
igorsk	0:b56b6a05cad4	645	* back soon (for example, if the destination IP address is ours. */
igorsk	0:b56b6a05cad4	646	update_arp_entry(netif, &iphdr_src, &(ethhdr->src), ETHARP_FLAG_FIND_ONLY);
igorsk	0:b56b6a05cad4	647	}
igorsk	0:b56b6a05cad4	648	#endif /* ETHARP_TRUST_IP_MAC */
igorsk	0:b56b6a05cad4	649
igorsk	0:b56b6a05cad4	650	/**
igorsk	0:b56b6a05cad4	651	* Responds to ARP requests to us. Upon ARP replies to us, add entry to cache
igorsk	0:b56b6a05cad4	652	* send out queued IP packets. Updates cache with snooped address pairs.
igorsk	0:b56b6a05cad4	653	*
igorsk	0:b56b6a05cad4	654	* Should be called for incoming ARP packets. The pbuf in the argument
igorsk	0:b56b6a05cad4	655	* is freed by this function.
igorsk	0:b56b6a05cad4	656	*
igorsk	0:b56b6a05cad4	657	* @param netif The lwIP network interface on which the ARP packet pbuf arrived.
igorsk	0:b56b6a05cad4	658	* @param ethaddr Ethernet address of netif.
igorsk	0:b56b6a05cad4	659	* @param p The ARP packet that arrived on netif. Is freed by this function.
igorsk	0:b56b6a05cad4	660	*
igorsk	0:b56b6a05cad4	661	* @return NULL
igorsk	0:b56b6a05cad4	662	*
igorsk	0:b56b6a05cad4	663	* @see pbuf_free()
igorsk	0:b56b6a05cad4	664	*/
igorsk	0:b56b6a05cad4	665	static void
igorsk	0:b56b6a05cad4	666	etharp_arp_input(struct netif netif, struct eth_addr ethaddr, struct pbuf *p)
igorsk	0:b56b6a05cad4	667	{
igorsk	0:b56b6a05cad4	668	struct etharp_hdr *hdr;
igorsk	0:b56b6a05cad4	669	struct eth_hdr *ethhdr;
igorsk	0:b56b6a05cad4	670	/* these are aligned properly, whereas the ARP header fields might not be */
igorsk	0:b56b6a05cad4	671	ip_addr_t sipaddr, dipaddr;
igorsk	0:b56b6a05cad4	672	u8_t for_us;
igorsk	0:b56b6a05cad4	673	#if LWIP_AUTOIP
igorsk	0:b56b6a05cad4	674	const u8_t * ethdst_hwaddr;
igorsk	0:b56b6a05cad4	675	#endif /* LWIP_AUTOIP */
igorsk	0:b56b6a05cad4	676
igorsk	0:b56b6a05cad4	677	LWIP_ERROR("netif != NULL", (netif != NULL), return;);
igorsk	0:b56b6a05cad4	678
igorsk	0:b56b6a05cad4	679	/* drop short ARP packets: we have to check for p->len instead of p->tot_len here
igorsk	0:b56b6a05cad4	680	since a struct etharp_hdr is pointed to p->payload, so it musn't be chained! */
igorsk	0:b56b6a05cad4	681	if (p->len < SIZEOF_ETHARP_PACKET) {
igorsk	0:b56b6a05cad4	682	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_WARNING,
igorsk	0:b56b6a05cad4	683	("etharp_arp_input: packet dropped, too short (%"S16_F"/%"S16_F")\n", p->tot_len,
igorsk	0:b56b6a05cad4	684	(s16_t)SIZEOF_ETHARP_PACKET));
igorsk	0:b56b6a05cad4	685	ETHARP_STATS_INC(etharp.lenerr);
igorsk	0:b56b6a05cad4	686	ETHARP_STATS_INC(etharp.drop);
igorsk	0:b56b6a05cad4	687	pbuf_free(p);
igorsk	0:b56b6a05cad4	688	return;
igorsk	0:b56b6a05cad4	689	}
igorsk	0:b56b6a05cad4	690
igorsk	0:b56b6a05cad4	691	ethhdr = (struct eth_hdr *)p->payload;
igorsk	0:b56b6a05cad4	692	hdr = (struct etharp_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
igorsk	0:b56b6a05cad4	693	#if ETHARP_SUPPORT_VLAN
igorsk	0:b56b6a05cad4	694	if (ethhdr->type == ETHTYPE_VLAN) {
igorsk	0:b56b6a05cad4	695	hdr = (struct etharp_hdr )(((u8_t)ethhdr) + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
igorsk	0:b56b6a05cad4	696	}
igorsk	0:b56b6a05cad4	697	#endif /* ETHARP_SUPPORT_VLAN */
igorsk	0:b56b6a05cad4	698
igorsk	0:b56b6a05cad4	699	/* RFC 826 "Packet Reception": */
igorsk	0:b56b6a05cad4	700	if ((hdr->hwtype != PP_HTONS(HWTYPE_ETHERNET)) \|\|
igorsk	0:b56b6a05cad4	701	(hdr->hwlen != ETHARP_HWADDR_LEN) \|\|
igorsk	0:b56b6a05cad4	702	(hdr->protolen != sizeof(ip_addr_t)) \|\|
igorsk	0:b56b6a05cad4	703	(hdr->proto != PP_HTONS(ETHTYPE_IP)) \|\|
igorsk	0:b56b6a05cad4	704	(ethhdr->type != PP_HTONS(ETHTYPE_ARP))) {
igorsk	0:b56b6a05cad4	705	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_WARNING,
igorsk	0:b56b6a05cad4	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",
igorsk	0:b56b6a05cad4	707	hdr->hwtype, hdr->hwlen, hdr->proto, hdr->protolen, ethhdr->type));
igorsk	0:b56b6a05cad4	708	ETHARP_STATS_INC(etharp.proterr);
igorsk	0:b56b6a05cad4	709	ETHARP_STATS_INC(etharp.drop);
igorsk	0:b56b6a05cad4	710	pbuf_free(p);
igorsk	0:b56b6a05cad4	711	return;
igorsk	0:b56b6a05cad4	712	}
igorsk	0:b56b6a05cad4	713	ETHARP_STATS_INC(etharp.recv);
igorsk	0:b56b6a05cad4	714
igorsk	0:b56b6a05cad4	715	#if LWIP_AUTOIP
igorsk	0:b56b6a05cad4	716	/* We have to check if a host already has configured our random
igorsk	0:b56b6a05cad4	717	* created link local address and continously check if there is
igorsk	0:b56b6a05cad4	718	* a host with this IP-address so we can detect collisions */
igorsk	0:b56b6a05cad4	719	autoip_arp_reply(netif, hdr);
igorsk	0:b56b6a05cad4	720	#endif /* LWIP_AUTOIP */
igorsk	0:b56b6a05cad4	721
igorsk	0:b56b6a05cad4	722	/* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
igorsk	0:b56b6a05cad4	723	* structure packing (not using structure copy which breaks strict-aliasing rules). */
igorsk	0:b56b6a05cad4	724	IPADDR2_COPY(&sipaddr, &hdr->sipaddr);
igorsk	0:b56b6a05cad4	725	IPADDR2_COPY(&dipaddr, &hdr->dipaddr);
igorsk	0:b56b6a05cad4	726
igorsk	0:b56b6a05cad4	727	/* this interface is not configured? */
igorsk	0:b56b6a05cad4	728	if (ip_addr_isany(&netif->ip_addr)) {
igorsk	0:b56b6a05cad4	729	for_us = 0;
igorsk	0:b56b6a05cad4	730	} else {
igorsk	0:b56b6a05cad4	731	/* ARP packet directed to us? */
igorsk	0:b56b6a05cad4	732	for_us = (u8_t)ip_addr_cmp(&dipaddr, &(netif->ip_addr));
igorsk	0:b56b6a05cad4	733	}
igorsk	0:b56b6a05cad4	734
igorsk	0:b56b6a05cad4	735	/* ARP message directed to us?
igorsk	0:b56b6a05cad4	736	-> add IP address in ARP cache; assume requester wants to talk to us,
igorsk	0:b56b6a05cad4	737	can result in directly sending the queued packets for this host.
igorsk	0:b56b6a05cad4	738	ARP message not directed to us?
igorsk	0:b56b6a05cad4	739	-> update the source IP address in the cache, if present */
igorsk	0:b56b6a05cad4	740	update_arp_entry(netif, &sipaddr, &(hdr->shwaddr),
igorsk	0:b56b6a05cad4	741	for_us ? ETHARP_FLAG_TRY_HARD : ETHARP_FLAG_FIND_ONLY);
igorsk	0:b56b6a05cad4	742
igorsk	0:b56b6a05cad4	743	/* now act on the message itself */
igorsk	0:b56b6a05cad4	744	switch (hdr->opcode) {
igorsk	0:b56b6a05cad4	745	/* ARP request? */
igorsk	0:b56b6a05cad4	746	case PP_HTONS(ARP_REQUEST):
igorsk	0:b56b6a05cad4	747	/* ARP request. If it asked for our address, we send out a
igorsk	0:b56b6a05cad4	748	* reply. In any case, we time-stamp any existing ARP entry,
igorsk	0:b56b6a05cad4	749	* and possiby send out an IP packet that was queued on it. */
igorsk	0:b56b6a05cad4	750
igorsk	0:b56b6a05cad4	751	LWIP_DEBUGF (ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP request\n"));
igorsk	0:b56b6a05cad4	752	/* ARP request for our address? */
igorsk	0:b56b6a05cad4	753	if (for_us) {
igorsk	0:b56b6a05cad4	754
igorsk	0:b56b6a05cad4	755	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: replying to ARP request for our IP address\n"));
igorsk	0:b56b6a05cad4	756	/* Re-use pbuf to send ARP reply.
igorsk	0:b56b6a05cad4	757	Since we are re-using an existing pbuf, we can't call etharp_raw since
igorsk	0:b56b6a05cad4	758	that would allocate a new pbuf. */
igorsk	0:b56b6a05cad4	759	hdr->opcode = htons(ARP_REPLY);
igorsk	0:b56b6a05cad4	760
igorsk	0:b56b6a05cad4	761	IPADDR2_COPY(&hdr->dipaddr, &hdr->sipaddr);
igorsk	0:b56b6a05cad4	762	IPADDR2_COPY(&hdr->sipaddr, &netif->ip_addr);
igorsk	0:b56b6a05cad4	763
igorsk	0:b56b6a05cad4	764	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
igorsk	0:b56b6a05cad4	765	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
igorsk	0:b56b6a05cad4	766	#if LWIP_AUTOIP
igorsk	0:b56b6a05cad4	767	/* If we are using Link-Local, all ARP packets that contain a Link-Local
igorsk	0:b56b6a05cad4	768	* 'sender IP address' MUST be sent using link-layer broadcast instead of
igorsk	0:b56b6a05cad4	769	* link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
igorsk	0:b56b6a05cad4	770	ethdst_hwaddr = ip_addr_islinklocal(&netif->ip_addr) ? (u8_t*)(ethbroadcast.addr) : hdr->shwaddr.addr;
igorsk	0:b56b6a05cad4	771	#endif /* LWIP_AUTOIP */
igorsk	0:b56b6a05cad4	772
igorsk	0:b56b6a05cad4	773	ETHADDR16_COPY(&hdr->dhwaddr, &hdr->shwaddr);
igorsk	0:b56b6a05cad4	774	#if LWIP_AUTOIP
igorsk	0:b56b6a05cad4	775	ETHADDR16_COPY(&ethhdr->dest, ethdst_hwaddr);
igorsk	0:b56b6a05cad4	776	#else /* LWIP_AUTOIP */
igorsk	0:b56b6a05cad4	777	ETHADDR16_COPY(&ethhdr->dest, &hdr->shwaddr);
igorsk	0:b56b6a05cad4	778	#endif /* LWIP_AUTOIP */
igorsk	0:b56b6a05cad4	779	ETHADDR16_COPY(&hdr->shwaddr, ethaddr);
igorsk	0:b56b6a05cad4	780	ETHADDR16_COPY(&ethhdr->src, ethaddr);
igorsk	0:b56b6a05cad4	781
igorsk	0:b56b6a05cad4	782	/* hwtype, hwaddr_len, proto, protolen and the type in the ethernet header
igorsk	0:b56b6a05cad4	783	are already correct, we tested that before */
igorsk	0:b56b6a05cad4	784
igorsk	0:b56b6a05cad4	785	/* return ARP reply */
igorsk	0:b56b6a05cad4	786	netif->linkoutput(netif, p);
igorsk	0:b56b6a05cad4	787	/* we are not configured? */
igorsk	0:b56b6a05cad4	788	} else if (ip_addr_isany(&netif->ip_addr)) {
igorsk	0:b56b6a05cad4	789	/* { for_us == 0 and netif->ip_addr.addr == 0 } */
igorsk	0:b56b6a05cad4	790	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: we are unconfigured, ARP request ignored.\n"));
igorsk	0:b56b6a05cad4	791	/* request was not directed to us */
igorsk	0:b56b6a05cad4	792	} else {
igorsk	0:b56b6a05cad4	793	/* { for_us == 0 and netif->ip_addr.addr != 0 } */
igorsk	0:b56b6a05cad4	794	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: ARP request was not for us.\n"));
igorsk	0:b56b6a05cad4	795	}
igorsk	0:b56b6a05cad4	796	break;
igorsk	0:b56b6a05cad4	797	case PP_HTONS(ARP_REPLY):
igorsk	0:b56b6a05cad4	798	/* ARP reply. We already updated the ARP cache earlier. */
igorsk	0:b56b6a05cad4	799	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP reply\n"));
igorsk	0:b56b6a05cad4	800	#if (LWIP_DHCP && DHCP_DOES_ARP_CHECK)
igorsk	0:b56b6a05cad4	801	/* DHCP wants to know about ARP replies from any host with an
igorsk	0:b56b6a05cad4	802	* IP address also offered to us by the DHCP server. We do not
igorsk	0:b56b6a05cad4	803	* want to take a duplicate IP address on a single network.
igorsk	0:b56b6a05cad4	804	* @todo How should we handle redundant (fail-over) interfaces? */
igorsk	0:b56b6a05cad4	805	dhcp_arp_reply(netif, &sipaddr);
igorsk	0:b56b6a05cad4	806	#endif /* (LWIP_DHCP && DHCP_DOES_ARP_CHECK) */
igorsk	0:b56b6a05cad4	807	break;
igorsk	0:b56b6a05cad4	808	default:
igorsk	0:b56b6a05cad4	809	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_arp_input: ARP unknown opcode type %"S16_F"\n", htons(hdr->opcode)));
igorsk	0:b56b6a05cad4	810	ETHARP_STATS_INC(etharp.err);
igorsk	0:b56b6a05cad4	811	break;
igorsk	0:b56b6a05cad4	812	}
igorsk	0:b56b6a05cad4	813	/* free ARP packet */
igorsk	0:b56b6a05cad4	814	pbuf_free(p);
igorsk	0:b56b6a05cad4	815	}
igorsk	0:b56b6a05cad4	816
igorsk	0:b56b6a05cad4	817	/**
igorsk	0:b56b6a05cad4	818	* Resolve and fill-in Ethernet address header for outgoing IP packet.
igorsk	0:b56b6a05cad4	819	*
igorsk	0:b56b6a05cad4	820	* For IP multicast and broadcast, corresponding Ethernet addresses
igorsk	0:b56b6a05cad4	821	* are selected and the packet is transmitted on the link.
igorsk	0:b56b6a05cad4	822	*
igorsk	0:b56b6a05cad4	823	* For unicast addresses, the packet is submitted to etharp_query(). In
igorsk	0:b56b6a05cad4	824	* case the IP address is outside the local network, the IP address of
igorsk	0:b56b6a05cad4	825	* the gateway is used.
igorsk	0:b56b6a05cad4	826	*
igorsk	0:b56b6a05cad4	827	* @param netif The lwIP network interface which the IP packet will be sent on.
igorsk	0:b56b6a05cad4	828	* @param q The pbuf(s) containing the IP packet to be sent.
igorsk	0:b56b6a05cad4	829	* @param ipaddr The IP address of the packet destination.
igorsk	0:b56b6a05cad4	830	*
igorsk	0:b56b6a05cad4	831	* @return
igorsk	0:b56b6a05cad4	832	* - ERR_RTE No route to destination (no gateway to external networks),
igorsk	0:b56b6a05cad4	833	* or the return type of either etharp_query() or etharp_send_ip().
igorsk	0:b56b6a05cad4	834	*/
igorsk	0:b56b6a05cad4	835	err_t
igorsk	0:b56b6a05cad4	836	etharp_output(struct netif netif, struct pbuf q, ip_addr_t *ipaddr)
igorsk	0:b56b6a05cad4	837	{
igorsk	0:b56b6a05cad4	838	struct eth_addr *dest, mcastaddr;
igorsk	0:b56b6a05cad4	839
igorsk	0:b56b6a05cad4	840	/* make room for Ethernet header - should not fail */
igorsk	0:b56b6a05cad4	841	if (pbuf_header(q, sizeof(struct eth_hdr)) != 0) {
igorsk	0:b56b6a05cad4	842	/* bail out */
igorsk	0:b56b6a05cad4	843	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_SERIOUS,
igorsk	0:b56b6a05cad4	844	("etharp_output: could not allocate room for header.\n"));
igorsk	0:b56b6a05cad4	845	LINK_STATS_INC(link.lenerr);
igorsk	0:b56b6a05cad4	846	return ERR_BUF;
igorsk	0:b56b6a05cad4	847	}
igorsk	0:b56b6a05cad4	848
igorsk	0:b56b6a05cad4	849	/* assume unresolved Ethernet address */
igorsk	0:b56b6a05cad4	850	dest = NULL;
igorsk	0:b56b6a05cad4	851	/* Determine on destination hardware address. Broadcasts and multicasts
igorsk	0:b56b6a05cad4	852	* are special, other IP addresses are looked up in the ARP table. */
igorsk	0:b56b6a05cad4	853
igorsk	0:b56b6a05cad4	854	/* broadcast destination IP address? */
igorsk	0:b56b6a05cad4	855	if (ip_addr_isbroadcast(ipaddr, netif)) {
igorsk	0:b56b6a05cad4	856	/* broadcast on Ethernet also */
igorsk	0:b56b6a05cad4	857	dest = (struct eth_addr *)&ethbroadcast;
igorsk	0:b56b6a05cad4	858	/* multicast destination IP address? */
igorsk	0:b56b6a05cad4	859	} else if (ip_addr_ismulticast(ipaddr)) {
igorsk	0:b56b6a05cad4	860	/* Hash IP multicast address to MAC address.*/
igorsk	0:b56b6a05cad4	861	mcastaddr.addr[0] = 0x01;
igorsk	0:b56b6a05cad4	862	mcastaddr.addr[1] = 0x00;
igorsk	0:b56b6a05cad4	863	mcastaddr.addr[2] = 0x5e;
igorsk	0:b56b6a05cad4	864	mcastaddr.addr[3] = ip4_addr2(ipaddr) & 0x7f;
igorsk	0:b56b6a05cad4	865	mcastaddr.addr[4] = ip4_addr3(ipaddr);
igorsk	0:b56b6a05cad4	866	mcastaddr.addr[5] = ip4_addr4(ipaddr);
igorsk	0:b56b6a05cad4	867	/* destination Ethernet address is multicast */
igorsk	0:b56b6a05cad4	868	dest = &mcastaddr;
igorsk	0:b56b6a05cad4	869	/* unicast destination IP address? */
igorsk	0:b56b6a05cad4	870	} else {
igorsk	0:b56b6a05cad4	871	/* outside local network? */
igorsk	0:b56b6a05cad4	872	if (!ip_addr_netcmp(ipaddr, &(netif->ip_addr), &(netif->netmask)) &&
igorsk	0:b56b6a05cad4	873	!ip_addr_islinklocal(ipaddr)) {
igorsk	0:b56b6a05cad4	874	/* interface has default gateway? */
igorsk	0:b56b6a05cad4	875	if (!ip_addr_isany(&netif->gw)) {
igorsk	0:b56b6a05cad4	876	/* send to hardware address of default gateway IP address */
igorsk	0:b56b6a05cad4	877	ipaddr = &(netif->gw);
igorsk	0:b56b6a05cad4	878	/* no default gateway available */
igorsk	0:b56b6a05cad4	879	} else {
igorsk	0:b56b6a05cad4	880	/* no route to destination error (default gateway missing) */
igorsk	0:b56b6a05cad4	881	return ERR_RTE;
igorsk	0:b56b6a05cad4	882	}
igorsk	0:b56b6a05cad4	883	}
igorsk	0:b56b6a05cad4	884	#if LWIP_NETIF_HWADDRHINT
igorsk	0:b56b6a05cad4	885	if (netif->addr_hint != NULL) {
igorsk	0:b56b6a05cad4	886	/* per-pcb cached entry was given */
igorsk	0:b56b6a05cad4	887	u8_t etharp_cached_entry = *(netif->addr_hint);
igorsk	0:b56b6a05cad4	888	if (etharp_cached_entry < ARP_TABLE_SIZE) {
igorsk	0:b56b6a05cad4	889	#endif /* LWIP_NETIF_HWADDRHINT */
igorsk	0:b56b6a05cad4	890	if ((arp_table[etharp_cached_entry].state == ETHARP_STATE_STABLE) &&
igorsk	0:b56b6a05cad4	891	(ip_addr_cmp(ipaddr, &arp_table[etharp_cached_entry].ipaddr))) {
igorsk	0:b56b6a05cad4	892	/* the per-pcb-cached entry is stable and the right one! */
igorsk	0:b56b6a05cad4	893	ETHARP_STATS_INC(etharp.cachehit);
igorsk	0:b56b6a05cad4	894	return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr),
igorsk	0:b56b6a05cad4	895	&arp_table[etharp_cached_entry].ethaddr);
igorsk	0:b56b6a05cad4	896	}
igorsk	0:b56b6a05cad4	897	#if LWIP_NETIF_HWADDRHINT
igorsk	0:b56b6a05cad4	898	}
igorsk	0:b56b6a05cad4	899	}
igorsk	0:b56b6a05cad4	900	#endif /* LWIP_NETIF_HWADDRHINT */
igorsk	0:b56b6a05cad4	901	/* queue on destination Ethernet address belonging to ipaddr */
igorsk	0:b56b6a05cad4	902	return etharp_query(netif, ipaddr, q);
igorsk	0:b56b6a05cad4	903	}
igorsk	0:b56b6a05cad4	904
igorsk	0:b56b6a05cad4	905	/* continuation for multicast/broadcast destinations */
igorsk	0:b56b6a05cad4	906	/* obtain source Ethernet address of the given interface */
igorsk	0:b56b6a05cad4	907	/* send packet directly on the link */
igorsk	0:b56b6a05cad4	908	return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr), dest);
igorsk	0:b56b6a05cad4	909	}
igorsk	0:b56b6a05cad4	910
igorsk	0:b56b6a05cad4	911	/**
igorsk	0:b56b6a05cad4	912	* Send an ARP request for the given IP address and/or queue a packet.
igorsk	0:b56b6a05cad4	913	*
igorsk	0:b56b6a05cad4	914	* If the IP address was not yet in the cache, a pending ARP cache entry
igorsk	0:b56b6a05cad4	915	* is added and an ARP request is sent for the given address. The packet
igorsk	0:b56b6a05cad4	916	* is queued on this entry.
igorsk	0:b56b6a05cad4	917	*
igorsk	0:b56b6a05cad4	918	* If the IP address was already pending in the cache, a new ARP request
igorsk	0:b56b6a05cad4	919	* is sent for the given address. The packet is queued on this entry.
igorsk	0:b56b6a05cad4	920	*
igorsk	0:b56b6a05cad4	921	* If the IP address was already stable in the cache, and a packet is
igorsk	0:b56b6a05cad4	922	* given, it is directly sent and no ARP request is sent out.
igorsk	0:b56b6a05cad4	923	*
igorsk	0:b56b6a05cad4	924	* If the IP address was already stable in the cache, and no packet is
igorsk	0:b56b6a05cad4	925	* given, an ARP request is sent out.
igorsk	0:b56b6a05cad4	926	*
igorsk	0:b56b6a05cad4	927	* @param netif The lwIP network interface on which ipaddr
igorsk	0:b56b6a05cad4	928	* must be queried for.
igorsk	0:b56b6a05cad4	929	* @param ipaddr The IP address to be resolved.
igorsk	0:b56b6a05cad4	930	* @param q If non-NULL, a pbuf that must be delivered to the IP address.
igorsk	0:b56b6a05cad4	931	* q is not freed by this function.
igorsk	0:b56b6a05cad4	932	*
igorsk	0:b56b6a05cad4	933	* @note q must only be ONE packet, not a packet queue!
igorsk	0:b56b6a05cad4	934	*
igorsk	0:b56b6a05cad4	935	* @return
igorsk	0:b56b6a05cad4	936	* - ERR_BUF Could not make room for Ethernet header.
igorsk	0:b56b6a05cad4	937	* - ERR_MEM Hardware address unknown, and no more ARP entries available
igorsk	0:b56b6a05cad4	938	* to query for address or queue the packet.
igorsk	0:b56b6a05cad4	939	* - ERR_MEM Could not queue packet due to memory shortage.
igorsk	0:b56b6a05cad4	940	* - ERR_RTE No route to destination (no gateway to external networks).
igorsk	0:b56b6a05cad4	941	* - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
igorsk	0:b56b6a05cad4	942	*
igorsk	0:b56b6a05cad4	943	*/
igorsk	0:b56b6a05cad4	944	err_t
igorsk	0:b56b6a05cad4	945	etharp_query(struct netif netif, ip_addr_t ipaddr, struct pbuf *q)
igorsk	0:b56b6a05cad4	946	{
igorsk	0:b56b6a05cad4	947	struct eth_addr * srcaddr = (struct eth_addr *)netif->hwaddr;
igorsk	0:b56b6a05cad4	948	err_t result = ERR_MEM;
igorsk	0:b56b6a05cad4	949	s8_t i; /* ARP entry index */
igorsk	0:b56b6a05cad4	950
igorsk	0:b56b6a05cad4	951	/* non-unicast address? */
igorsk	0:b56b6a05cad4	952	if (ip_addr_isbroadcast(ipaddr, netif) \|\|
igorsk	0:b56b6a05cad4	953	ip_addr_ismulticast(ipaddr) \|\|
igorsk	0:b56b6a05cad4	954	ip_addr_isany(ipaddr)) {
igorsk	0:b56b6a05cad4	955	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: will not add non-unicast IP address to ARP cache\n"));
igorsk	0:b56b6a05cad4	956	return ERR_ARG;
igorsk	0:b56b6a05cad4	957	}
igorsk	0:b56b6a05cad4	958
igorsk	0:b56b6a05cad4	959	/* find entry in ARP cache, ask to create entry if queueing packet */
igorsk	0:b56b6a05cad4	960	i = find_entry(ipaddr, ETHARP_FLAG_TRY_HARD);
igorsk	0:b56b6a05cad4	961
igorsk	0:b56b6a05cad4	962	/* could not find or create entry? */
igorsk	0:b56b6a05cad4	963	if (i < 0) {
igorsk	0:b56b6a05cad4	964	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: could not create ARP entry\n"));
igorsk	0:b56b6a05cad4	965	if (q) {
igorsk	0:b56b6a05cad4	966	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: packet dropped\n"));
igorsk	0:b56b6a05cad4	967	ETHARP_STATS_INC(etharp.memerr);
igorsk	0:b56b6a05cad4	968	}
igorsk	0:b56b6a05cad4	969	return (err_t)i;
igorsk	0:b56b6a05cad4	970	}
igorsk	0:b56b6a05cad4	971
igorsk	0:b56b6a05cad4	972	/* mark a fresh entry as pending (we just sent a request) */
igorsk	0:b56b6a05cad4	973	if (arp_table[i].state == ETHARP_STATE_EMPTY) {
igorsk	0:b56b6a05cad4	974	arp_table[i].state = ETHARP_STATE_PENDING;
igorsk	0:b56b6a05cad4	975	}
igorsk	0:b56b6a05cad4	976
igorsk	0:b56b6a05cad4	977	/* { i is either a STABLE or (new or existing) PENDING entry } */
igorsk	0:b56b6a05cad4	978	LWIP_ASSERT("arp_table[i].state == PENDING or STABLE",
igorsk	0:b56b6a05cad4	979	((arp_table[i].state == ETHARP_STATE_PENDING) \|\|
igorsk	0:b56b6a05cad4	980	(arp_table[i].state == ETHARP_STATE_STABLE)));
igorsk	0:b56b6a05cad4	981
igorsk	0:b56b6a05cad4	982	/* do we have a pending entry? or an implicit query request? */
igorsk	0:b56b6a05cad4	983	if ((arp_table[i].state == ETHARP_STATE_PENDING) \|\| (q == NULL)) {
igorsk	0:b56b6a05cad4	984	/* try to resolve it; send out ARP request */
igorsk	0:b56b6a05cad4	985	result = etharp_request(netif, ipaddr);
igorsk	0:b56b6a05cad4	986	if (result != ERR_OK) {
igorsk	0:b56b6a05cad4	987	/* ARP request couldn't be sent */
igorsk	0:b56b6a05cad4	988	/* We don't re-send arp request in etharp_tmr, but we still queue packets,
igorsk	0:b56b6a05cad4	989	since this failure could be temporary, and the next packet calling
igorsk	0:b56b6a05cad4	990	etharp_query again could lead to sending the queued packets. */
igorsk	0:b56b6a05cad4	991	}
igorsk	0:b56b6a05cad4	992	if (q == NULL) {
igorsk	0:b56b6a05cad4	993	return result;
igorsk	0:b56b6a05cad4	994	}
igorsk	0:b56b6a05cad4	995	}
igorsk	0:b56b6a05cad4	996
igorsk	0:b56b6a05cad4	997	/* packet given? */
igorsk	0:b56b6a05cad4	998	LWIP_ASSERT("q != NULL", q != NULL);
igorsk	0:b56b6a05cad4	999	/* stable entry? */
igorsk	0:b56b6a05cad4	1000	if (arp_table[i].state == ETHARP_STATE_STABLE) {
igorsk	0:b56b6a05cad4	1001	/* we have a valid IP->Ethernet address mapping */
igorsk	0:b56b6a05cad4	1002	ETHARP_SET_HINT(netif, i);
igorsk	0:b56b6a05cad4	1003	/* send the packet */
igorsk	0:b56b6a05cad4	1004	result = etharp_send_ip(netif, q, srcaddr, &(arp_table[i].ethaddr));
igorsk	0:b56b6a05cad4	1005	/* pending entry? (either just created or already pending */
igorsk	0:b56b6a05cad4	1006	} else if (arp_table[i].state == ETHARP_STATE_PENDING) {
igorsk	0:b56b6a05cad4	1007	#if ARP_QUEUEING /* queue the given q packet */
igorsk	0:b56b6a05cad4	1008	struct pbuf *p;
igorsk	0:b56b6a05cad4	1009	int copy_needed = 0;
igorsk	0:b56b6a05cad4	1010	/* IF q includes a PBUF_REF, PBUF_POOL or PBUF_RAM, we have no choice but
igorsk	0:b56b6a05cad4	1011	* to copy the whole queue into a new PBUF_RAM (see bug #11400)
igorsk	0:b56b6a05cad4	1012	* PBUF_ROMs can be left as they are, since ROM must not get changed. */
igorsk	0:b56b6a05cad4	1013	p = q;
igorsk	0:b56b6a05cad4	1014	while (p) {
igorsk	0:b56b6a05cad4	1015	LWIP_ASSERT("no packet queues allowed!", (p->len != p->tot_len) \|\| (p->next == 0));
igorsk	0:b56b6a05cad4	1016	if(p->type != PBUF_ROM) {
igorsk	0:b56b6a05cad4	1017	copy_needed = 1;
igorsk	0:b56b6a05cad4	1018	break;
igorsk	0:b56b6a05cad4	1019	}
igorsk	0:b56b6a05cad4	1020	p = p->next;
igorsk	0:b56b6a05cad4	1021	}
igorsk	0:b56b6a05cad4	1022	if(copy_needed) {
igorsk	0:b56b6a05cad4	1023	/* copy the whole packet into new pbufs */
igorsk	0:b56b6a05cad4	1024	p = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
igorsk	0:b56b6a05cad4	1025	if(p != NULL) {
igorsk	0:b56b6a05cad4	1026	if (pbuf_copy(p, q) != ERR_OK) {
igorsk	0:b56b6a05cad4	1027	pbuf_free(p);
igorsk	0:b56b6a05cad4	1028	p = NULL;
igorsk	0:b56b6a05cad4	1029	}
igorsk	0:b56b6a05cad4	1030	}
igorsk	0:b56b6a05cad4	1031	} else {
igorsk	0:b56b6a05cad4	1032	/* referencing the old pbuf is enough */
igorsk	0:b56b6a05cad4	1033	p = q;
igorsk	0:b56b6a05cad4	1034	pbuf_ref(p);
igorsk	0:b56b6a05cad4	1035	}
igorsk	0:b56b6a05cad4	1036	/* packet could be taken over? */
igorsk	0:b56b6a05cad4	1037	if (p != NULL) {
igorsk	0:b56b6a05cad4	1038	/* queue packet ... */
igorsk	0:b56b6a05cad4	1039	struct etharp_q_entry *new_entry;
igorsk	0:b56b6a05cad4	1040	/* allocate a new arp queue entry */
igorsk	0:b56b6a05cad4	1041	new_entry = (struct etharp_q_entry *)memp_malloc(MEMP_ARP_QUEUE);
igorsk	0:b56b6a05cad4	1042	if (new_entry != NULL) {
igorsk	0:b56b6a05cad4	1043	new_entry->next = 0;
igorsk	0:b56b6a05cad4	1044	new_entry->p = p;
igorsk	0:b56b6a05cad4	1045	if(arp_table[i].q != NULL) {
igorsk	0:b56b6a05cad4	1046	/* queue was already existent, append the new entry to the end */
igorsk	0:b56b6a05cad4	1047	struct etharp_q_entry *r;
igorsk	0:b56b6a05cad4	1048	r = arp_table[i].q;
igorsk	0:b56b6a05cad4	1049	while (r->next != NULL) {
igorsk	0:b56b6a05cad4	1050	r = r->next;
igorsk	0:b56b6a05cad4	1051	}
igorsk	0:b56b6a05cad4	1052	r->next = new_entry;
igorsk	0:b56b6a05cad4	1053	} else {
igorsk	0:b56b6a05cad4	1054	/* queue did not exist, first item in queue */
igorsk	0:b56b6a05cad4	1055	arp_table[i].q = new_entry;
igorsk	0:b56b6a05cad4	1056	}
igorsk	0:b56b6a05cad4	1057	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: queued packet %p on ARP entry %"S16_F"\n", (void *)q, (s16_t)i));
igorsk	0:b56b6a05cad4	1058	result = ERR_OK;
igorsk	0:b56b6a05cad4	1059	} else {
igorsk	0:b56b6a05cad4	1060	/* the pool MEMP_ARP_QUEUE is empty */
igorsk	0:b56b6a05cad4	1061	pbuf_free(p);
igorsk	0:b56b6a05cad4	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));
igorsk	0:b56b6a05cad4	1063	/* { result == ERR_MEM } through initialization */
igorsk	0:b56b6a05cad4	1064	}
igorsk	0:b56b6a05cad4	1065	} else {
igorsk	0:b56b6a05cad4	1066	ETHARP_STATS_INC(etharp.memerr);
igorsk	0:b56b6a05cad4	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));
igorsk	0:b56b6a05cad4	1068	/* { result == ERR_MEM } through initialization */
igorsk	0:b56b6a05cad4	1069	}
igorsk	0:b56b6a05cad4	1070	#else /* ARP_QUEUEING */
igorsk	0:b56b6a05cad4	1071	/* q && state == PENDING && ARP_QUEUEING == 0 => result = ERR_MEM */
igorsk	0:b56b6a05cad4	1072	/* { result == ERR_MEM } through initialization */
igorsk	0:b56b6a05cad4	1073	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_query: Ethernet destination address unknown, queueing disabled, packet %p dropped\n", (void *)q));
igorsk	0:b56b6a05cad4	1074	#endif /* ARP_QUEUEING */
igorsk	0:b56b6a05cad4	1075	}
igorsk	0:b56b6a05cad4	1076	return result;
igorsk	0:b56b6a05cad4	1077	}
igorsk	0:b56b6a05cad4	1078
igorsk	0:b56b6a05cad4	1079	/**
igorsk	0:b56b6a05cad4	1080	* Send a raw ARP packet (opcode and all addresses can be modified)
igorsk	0:b56b6a05cad4	1081	*
igorsk	0:b56b6a05cad4	1082	* @param netif the lwip network interface on which to send the ARP packet
igorsk	0:b56b6a05cad4	1083	* @param ethsrc_addr the source MAC address for the ethernet header
igorsk	0:b56b6a05cad4	1084	* @param ethdst_addr the destination MAC address for the ethernet header
igorsk	0:b56b6a05cad4	1085	* @param hwsrc_addr the source MAC address for the ARP protocol header
igorsk	0:b56b6a05cad4	1086	* @param ipsrc_addr the source IP address for the ARP protocol header
igorsk	0:b56b6a05cad4	1087	* @param hwdst_addr the destination MAC address for the ARP protocol header
igorsk	0:b56b6a05cad4	1088	* @param ipdst_addr the destination IP address for the ARP protocol header
igorsk	0:b56b6a05cad4	1089	* @param opcode the type of the ARP packet
igorsk	0:b56b6a05cad4	1090	* @return ERR_OK if the ARP packet has been sent
igorsk	0:b56b6a05cad4	1091	* ERR_MEM if the ARP packet couldn't be allocated
igorsk	0:b56b6a05cad4	1092	* any other err_t on failure
igorsk	0:b56b6a05cad4	1093	*/
igorsk	0:b56b6a05cad4	1094	#if !LWIP_AUTOIP
igorsk	0:b56b6a05cad4	1095	static
igorsk	0:b56b6a05cad4	1096	#endif /* LWIP_AUTOIP */
igorsk	0:b56b6a05cad4	1097	err_t
igorsk	0:b56b6a05cad4	1098	etharp_raw(struct netif netif, const struct eth_addr ethsrc_addr,
igorsk	0:b56b6a05cad4	1099	const struct eth_addr *ethdst_addr,
igorsk	0:b56b6a05cad4	1100	const struct eth_addr hwsrc_addr, const ip_addr_t ipsrc_addr,
igorsk	0:b56b6a05cad4	1101	const struct eth_addr hwdst_addr, const ip_addr_t ipdst_addr,
igorsk	0:b56b6a05cad4	1102	const u16_t opcode)
igorsk	0:b56b6a05cad4	1103	{
igorsk	0:b56b6a05cad4	1104	struct pbuf *p;
igorsk	0:b56b6a05cad4	1105	err_t result = ERR_OK;
igorsk	0:b56b6a05cad4	1106	struct eth_hdr *ethhdr;
igorsk	0:b56b6a05cad4	1107	struct etharp_hdr *hdr;
igorsk	0:b56b6a05cad4	1108	#if LWIP_AUTOIP
igorsk	0:b56b6a05cad4	1109	const u8_t * ethdst_hwaddr;
igorsk	0:b56b6a05cad4	1110	#endif /* LWIP_AUTOIP */
igorsk	0:b56b6a05cad4	1111
igorsk	0:b56b6a05cad4	1112	/* allocate a pbuf for the outgoing ARP request packet */
igorsk	0:b56b6a05cad4	1113	p = pbuf_alloc(PBUF_RAW, SIZEOF_ETHARP_PACKET, PBUF_RAM);
igorsk	0:b56b6a05cad4	1114	/* could allocate a pbuf for an ARP request? */
igorsk	0:b56b6a05cad4	1115	if (p == NULL) {
igorsk	0:b56b6a05cad4	1116	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_SERIOUS,
igorsk	0:b56b6a05cad4	1117	("etharp_raw: could not allocate pbuf for ARP request.\n"));
igorsk	0:b56b6a05cad4	1118	ETHARP_STATS_INC(etharp.memerr);
igorsk	0:b56b6a05cad4	1119	return ERR_MEM;
igorsk	0:b56b6a05cad4	1120	}
igorsk	0:b56b6a05cad4	1121	LWIP_ASSERT("check that first pbuf can hold struct etharp_hdr",
igorsk	0:b56b6a05cad4	1122	(p->len >= SIZEOF_ETHARP_PACKET));
igorsk	0:b56b6a05cad4	1123
igorsk	0:b56b6a05cad4	1124	ethhdr = (struct eth_hdr *)p->payload;
igorsk	0:b56b6a05cad4	1125	hdr = (struct etharp_hdr )((u8_t)ethhdr + SIZEOF_ETH_HDR);
igorsk	0:b56b6a05cad4	1126	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_raw: sending raw ARP packet.\n"));
igorsk	0:b56b6a05cad4	1127	hdr->opcode = htons(opcode);
igorsk	0:b56b6a05cad4	1128
igorsk	0:b56b6a05cad4	1129	LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
igorsk	0:b56b6a05cad4	1130	(netif->hwaddr_len == ETHARP_HWADDR_LEN));
igorsk	0:b56b6a05cad4	1131	#if LWIP_AUTOIP
igorsk	0:b56b6a05cad4	1132	/* If we are using Link-Local, all ARP packets that contain a Link-Local
igorsk	0:b56b6a05cad4	1133	* 'sender IP address' MUST be sent using link-layer broadcast instead of
igorsk	0:b56b6a05cad4	1134	* link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
igorsk	0:b56b6a05cad4	1135	ethdst_hwaddr = ip_addr_islinklocal(ipsrc_addr) ? (u8_t*)(ethbroadcast.addr) : ethdst_addr->addr;
igorsk	0:b56b6a05cad4	1136	#endif /* LWIP_AUTOIP */
igorsk	0:b56b6a05cad4	1137	/* Write the ARP MAC-Addresses */
igorsk	0:b56b6a05cad4	1138	ETHADDR16_COPY(&hdr->shwaddr, hwsrc_addr);
igorsk	0:b56b6a05cad4	1139	ETHADDR16_COPY(&hdr->dhwaddr, hwdst_addr);
igorsk	0:b56b6a05cad4	1140	/* Write the Ethernet MAC-Addresses */
igorsk	0:b56b6a05cad4	1141	#if LWIP_AUTOIP
igorsk	0:b56b6a05cad4	1142	ETHADDR16_COPY(&ethhdr->dest, ethdst_hwaddr);
igorsk	0:b56b6a05cad4	1143	#else /* LWIP_AUTOIP */
igorsk	0:b56b6a05cad4	1144	ETHADDR16_COPY(&ethhdr->dest, ethdst_addr);
igorsk	0:b56b6a05cad4	1145	#endif /* LWIP_AUTOIP */
igorsk	0:b56b6a05cad4	1146	ETHADDR16_COPY(&ethhdr->src, ethsrc_addr);
igorsk	0:b56b6a05cad4	1147	/* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
igorsk	0:b56b6a05cad4	1148	* structure packing. */
igorsk	0:b56b6a05cad4	1149	IPADDR2_COPY(&hdr->sipaddr, ipsrc_addr);
igorsk	0:b56b6a05cad4	1150	IPADDR2_COPY(&hdr->dipaddr, ipdst_addr);
igorsk	0:b56b6a05cad4	1151
igorsk	0:b56b6a05cad4	1152	hdr->hwtype = PP_HTONS(HWTYPE_ETHERNET);
igorsk	0:b56b6a05cad4	1153	hdr->proto = PP_HTONS(ETHTYPE_IP);
igorsk	0:b56b6a05cad4	1154	/* set hwlen and protolen */
igorsk	0:b56b6a05cad4	1155	hdr->hwlen = ETHARP_HWADDR_LEN;
igorsk	0:b56b6a05cad4	1156	hdr->protolen = sizeof(ip_addr_t);
igorsk	0:b56b6a05cad4	1157
igorsk	0:b56b6a05cad4	1158	ethhdr->type = PP_HTONS(ETHTYPE_ARP);
igorsk	0:b56b6a05cad4	1159	/* send ARP query */
igorsk	0:b56b6a05cad4	1160	result = netif->linkoutput(netif, p);
igorsk	0:b56b6a05cad4	1161	ETHARP_STATS_INC(etharp.xmit);
igorsk	0:b56b6a05cad4	1162	/* free ARP query packet */
igorsk	0:b56b6a05cad4	1163	pbuf_free(p);
igorsk	0:b56b6a05cad4	1164	p = NULL;
igorsk	0:b56b6a05cad4	1165	/* could not allocate pbuf for ARP request */
igorsk	0:b56b6a05cad4	1166
igorsk	0:b56b6a05cad4	1167	return result;
igorsk	0:b56b6a05cad4	1168	}
igorsk	0:b56b6a05cad4	1169
igorsk	0:b56b6a05cad4	1170	/**
igorsk	0:b56b6a05cad4	1171	* Send an ARP request packet asking for ipaddr.
igorsk	0:b56b6a05cad4	1172	*
igorsk	0:b56b6a05cad4	1173	* @param netif the lwip network interface on which to send the request
igorsk	0:b56b6a05cad4	1174	* @param ipaddr the IP address for which to ask
igorsk	0:b56b6a05cad4	1175	* @return ERR_OK if the request has been sent
igorsk	0:b56b6a05cad4	1176	* ERR_MEM if the ARP packet couldn't be allocated
igorsk	0:b56b6a05cad4	1177	* any other err_t on failure
igorsk	0:b56b6a05cad4	1178	*/
igorsk	0:b56b6a05cad4	1179	err_t
igorsk	0:b56b6a05cad4	1180	etharp_request(struct netif netif, ip_addr_t ipaddr)
igorsk	0:b56b6a05cad4	1181	{
igorsk	0:b56b6a05cad4	1182	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE, ("etharp_request: sending ARP request.\n"));
igorsk	0:b56b6a05cad4	1183	return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, &ethbroadcast,
igorsk	0:b56b6a05cad4	1184	(struct eth_addr *)netif->hwaddr, &netif->ip_addr, &ethzero,
igorsk	0:b56b6a05cad4	1185	ipaddr, ARP_REQUEST);
igorsk	0:b56b6a05cad4	1186	}
igorsk	0:b56b6a05cad4	1187	#endif /* LWIP_ARP */
igorsk	0:b56b6a05cad4	1188
igorsk	0:b56b6a05cad4	1189	/**
igorsk	0:b56b6a05cad4	1190	* Process received ethernet frames. Using this function instead of directly
igorsk	0:b56b6a05cad4	1191	* calling ip_input and passing ARP frames through etharp in ethernetif_input,
igorsk	0:b56b6a05cad4	1192	* the ARP cache is protected from concurrent access.
igorsk	0:b56b6a05cad4	1193	*
igorsk	0:b56b6a05cad4	1194	* @param p the recevied packet, p->payload pointing to the ethernet header
igorsk	0:b56b6a05cad4	1195	* @param netif the network interface on which the packet was received
igorsk	0:b56b6a05cad4	1196	*/
igorsk	0:b56b6a05cad4	1197	err_t
igorsk	0:b56b6a05cad4	1198	ethernet_input(struct pbuf p, struct netif netif)
igorsk	0:b56b6a05cad4	1199	{
igorsk	0:b56b6a05cad4	1200	struct eth_hdr* ethhdr;
igorsk	0:b56b6a05cad4	1201	u16_t type;
igorsk	0:b56b6a05cad4	1202
igorsk	0:b56b6a05cad4	1203	/* points to packet payload, which starts with an Ethernet header */
igorsk	0:b56b6a05cad4	1204	ethhdr = (struct eth_hdr *)p->payload;
igorsk	0:b56b6a05cad4	1205	LWIP_DEBUGF(ETHARP_DEBUG \| LWIP_DBG_TRACE,
igorsk	0:b56b6a05cad4	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",
igorsk	0:b56b6a05cad4	1207	(unsigned)ethhdr->dest.addr[0], (unsigned)ethhdr->dest.addr[1], (unsigned)ethhdr->dest.addr[2],
igorsk	0:b56b6a05cad4	1208	(unsigned)ethhdr->dest.addr[3], (unsigned)ethhdr->dest.addr[4], (unsigned)ethhdr->dest.addr[5],
igorsk	0:b56b6a05cad4	1209	(unsigned)ethhdr->src.addr[0], (unsigned)ethhdr->src.addr[1], (unsigned)ethhdr->src.addr[2],
igorsk	0:b56b6a05cad4	1210	(unsigned)ethhdr->src.addr[3], (unsigned)ethhdr->src.addr[4], (unsigned)ethhdr->src.addr[5],
igorsk	0:b56b6a05cad4	1211	(unsigned)htons(ethhdr->type)));
igorsk	0:b56b6a05cad4	1212
igorsk	0:b56b6a05cad4	1213	type = ethhdr->type;
igorsk	0:b56b6a05cad4	1214	#if ETHARP_SUPPORT_VLAN
igorsk	0:b56b6a05cad4	1215	if (type == PP_HTONS(ETHTYPE_VLAN)) {
igorsk	0:b56b6a05cad4	1216	struct eth_vlan_hdr vlan = (struct eth_vlan_hdr)(((char*)ethhdr) + SIZEOF_ETH_HDR);
igorsk	0:b56b6a05cad4	1217	#ifdef ETHARP_VLAN_CHECK /* if not, allow all VLANs */
igorsk	0:b56b6a05cad4	1218	if (VLAN_ID(vlan) != ETHARP_VLAN_CHECK) {
igorsk	0:b56b6a05cad4	1219	/* silently ignore this packet: not for our VLAN */
igorsk	0:b56b6a05cad4	1220	pbuf_free(p);
igorsk	0:b56b6a05cad4	1221	return ERR_OK;
igorsk	0:b56b6a05cad4	1222	}
igorsk	0:b56b6a05cad4	1223	#endif /* ETHARP_VLAN_CHECK */
igorsk	0:b56b6a05cad4	1224	type = vlan->tpid;
igorsk	0:b56b6a05cad4	1225	}
igorsk	0:b56b6a05cad4	1226	#endif /* ETHARP_SUPPORT_VLAN */
igorsk	0:b56b6a05cad4	1227
igorsk	0:b56b6a05cad4	1228	#if LWIP_ARP_FILTER_NETIF
igorsk	0:b56b6a05cad4	1229	netif = LWIP_ARP_FILTER_NETIF_FN(p, netif, htons(type));
igorsk	0:b56b6a05cad4	1230	#endif /* LWIP_ARP_FILTER_NETIF*/
igorsk	0:b56b6a05cad4	1231
igorsk	0:b56b6a05cad4	1232	switch (type) {
igorsk	0:b56b6a05cad4	1233	#if LWIP_ARP
igorsk	0:b56b6a05cad4	1234	/* IP packet? */
igorsk	0:b56b6a05cad4	1235	case PP_HTONS(ETHTYPE_IP):
igorsk	0:b56b6a05cad4	1236	if (!(netif->flags & NETIF_FLAG_ETHARP)) {
igorsk	0:b56b6a05cad4	1237	goto free_and_return;
igorsk	0:b56b6a05cad4	1238	}
igorsk	0:b56b6a05cad4	1239	#if ETHARP_TRUST_IP_MAC
igorsk	0:b56b6a05cad4	1240	/* update ARP table */
igorsk	0:b56b6a05cad4	1241	etharp_ip_input(netif, p);
igorsk	0:b56b6a05cad4	1242	#endif /* ETHARP_TRUST_IP_MAC */
igorsk	0:b56b6a05cad4	1243	/* skip Ethernet header */
igorsk	0:b56b6a05cad4	1244	if(pbuf_header(p, -(s16_t)SIZEOF_ETH_HDR)) {
igorsk	0:b56b6a05cad4	1245	LWIP_ASSERT("Can't move over header in packet", 0);
igorsk	0:b56b6a05cad4	1246	goto free_and_return;
igorsk	0:b56b6a05cad4	1247	} else {
igorsk	0:b56b6a05cad4	1248	/* pass to IP layer */
igorsk	0:b56b6a05cad4	1249	ip_input(p, netif);
igorsk	0:b56b6a05cad4	1250	}
igorsk	0:b56b6a05cad4	1251	break;
igorsk	0:b56b6a05cad4	1252
igorsk	0:b56b6a05cad4	1253	case PP_HTONS(ETHTYPE_ARP):
igorsk	0:b56b6a05cad4	1254	if (!(netif->flags & NETIF_FLAG_ETHARP)) {
igorsk	0:b56b6a05cad4	1255	goto free_and_return;
igorsk	0:b56b6a05cad4	1256	}
igorsk	0:b56b6a05cad4	1257	/* pass p to ARP module */
igorsk	0:b56b6a05cad4	1258	etharp_arp_input(netif, (struct eth_addr*)(netif->hwaddr), p);
igorsk	0:b56b6a05cad4	1259	break;
igorsk	0:b56b6a05cad4	1260	#endif /* LWIP_ARP */
igorsk	0:b56b6a05cad4	1261	#if PPPOE_SUPPORT
igorsk	0:b56b6a05cad4	1262	case PP_HTONS(ETHTYPE_PPPOEDISC): /* PPP Over Ethernet Discovery Stage */
igorsk	0:b56b6a05cad4	1263	pppoe_disc_input(netif, p);
igorsk	0:b56b6a05cad4	1264	break;
igorsk	0:b56b6a05cad4	1265
igorsk	0:b56b6a05cad4	1266	case PP_HTONS(ETHTYPE_PPPOE): /* PPP Over Ethernet Session Stage */
igorsk	0:b56b6a05cad4	1267	pppoe_data_input(netif, p);
igorsk	0:b56b6a05cad4	1268	break;
igorsk	0:b56b6a05cad4	1269	#endif /* PPPOE_SUPPORT */
igorsk	0:b56b6a05cad4	1270
igorsk	0:b56b6a05cad4	1271	default:
igorsk	0:b56b6a05cad4	1272	ETHARP_STATS_INC(etharp.proterr);
igorsk	0:b56b6a05cad4	1273	ETHARP_STATS_INC(etharp.drop);
igorsk	0:b56b6a05cad4	1274	goto free_and_return;
igorsk	0:b56b6a05cad4	1275	}
igorsk	0:b56b6a05cad4	1276
igorsk	0:b56b6a05cad4	1277	/* This means the pbuf is freed or consumed,
igorsk	0:b56b6a05cad4	1278	so the caller doesn't have to free it again */
igorsk	0:b56b6a05cad4	1279	return ERR_OK;
igorsk	0:b56b6a05cad4	1280
igorsk	0:b56b6a05cad4	1281	free_and_return:
igorsk	0:b56b6a05cad4	1282	pbuf_free(p);
igorsk	0:b56b6a05cad4	1283	return ERR_OK;
igorsk	0:b56b6a05cad4	1284	}
igorsk	0:b56b6a05cad4	1285	#endif /* LWIP_ARP \|\| LWIP_ETHERNET */

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Type:	Program
Created:	29 Jun 2011
Imports:	167
Forks:	0
Commits:	1
Dependents:	0
Dependencies:	0
Followers:	3

lwip/netif/etharp.c@0:b56b6a05cad4, 2011-06-29 (annotated)

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