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- /**
- * @file
- * Address Resolution Protocol module for IP over Ethernet
- *
- * Functionally, ARP is divided into two parts. The first maps an IP address
- * to a physical address when sending a packet, and the second part answers
- * requests from other machines for our physical address.
- *
- * This implementation complies with RFC 826 (Ethernet ARP). It supports
- * Gratuitious ARP from RFC3220 (IP Mobility Support for IPv4) section 4.6
- * if an interface calls etharp_gratuitous(our_netif) upon address change.
- */
- /*
- * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
- * Copyright (c) 2003-2004 Leon Woestenberg <leon.woestenberg@axon.tv>
- * Copyright (c) 2003-2004 Axon Digital Design B.V., The Netherlands.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without modification,
- * are permitted provided that the following conditions are met:
- *
- * 1. Redistributions of source code must retain the above copyright notice,
- * this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright notice,
- * this list of conditions and the following disclaimer in the documentation
- * and/or other materials provided with the distribution.
- * 3. The name of the author may not be used to endorse or promote products
- * derived from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
- * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
- * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
- * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
- * OF SUCH DAMAGE.
- *
- * This file is part of the lwIP TCP/IP stack.
- *
- */
- #include "lwip/opt.h"
- #if LWIP_ARP || LWIP_ETHERNET
- #include "lwip/ip_addr.h"
- #include "lwip/def.h"
- #include "lwip/ip.h"
- #include "lwip/stats.h"
- #include "lwip/snmp.h"
- #include "lwip/dhcp.h"
- #include "lwip/autoip.h"
- #include "netif/etharp.h"
- #if PPPOE_SUPPORT
- #include "netif/ppp_oe.h"
- #endif /* PPPOE_SUPPORT */
- #include <string.h>
- #ifdef MEMLEAK_DEBUG
- static const char mem_debug_file[] ICACHE_RODATA_ATTR = __FILE__;
- #endif
- const struct eth_addr ethbroadcast = {{0xff,0xff,0xff,0xff,0xff,0xff}};
- const struct eth_addr ethzero = {{0,0,0,0,0,0}};
- #if LWIP_ARP /* don't build if not configured for use in lwipopts.h */
- /** the time an ARP entry stays valid after its last update,
- * for ARP_TMR_INTERVAL = 5000, this is
- * (240 * 5) seconds = 20 minutes.
- */
- #define ARP_MAXAGE 240
- /** Re-request a used ARP entry 1 minute before it would expire to prevent
- * breaking a steadily used connection because the ARP entry timed out. */
- #define ARP_AGE_REREQUEST_USED (ARP_MAXAGE - 12)
- /** the time an ARP entry stays pending after first request,
- * for ARP_TMR_INTERVAL = 5000, this is
- * (2 * 5) seconds = 10 seconds.
- *
- * @internal Keep this number at least 2, otherwise it might
- * run out instantly if the timeout occurs directly after a request.
- */
- #define ARP_MAXPENDING 2
- #define HWTYPE_ETHERNET 1
- enum etharp_state {
- ETHARP_STATE_EMPTY = 0,
- ETHARP_STATE_PENDING,
- ETHARP_STATE_STABLE,
- ETHARP_STATE_STABLE_REREQUESTING
- };
- struct etharp_entry {
- #if ARP_QUEUEING
- /** Pointer to queue of pending outgoing packets on this ARP entry. */
- struct etharp_q_entry *q;
- #else /* ARP_QUEUEING */
- /** Pointer to a single pending outgoing packet on this ARP entry. */
- struct pbuf *q;
- #endif /* ARP_QUEUEING */
- ip_addr_t ipaddr;
- struct eth_addr ethaddr;
- #if LWIP_SNMP || LWIP_ARP
- struct netif *netif;
- #endif /* LWIP_SNMP */
- u8_t state;
- u8_t ctime;
- #if ETHARP_SUPPORT_STATIC_ENTRIES
- u8_t static_entry;
- #endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
- };
- static struct etharp_entry arp_table[ARP_TABLE_SIZE];
- #if !LWIP_NETIF_HWADDRHINT
- static u8_t etharp_cached_entry;
- #endif /* !LWIP_NETIF_HWADDRHINT */
- /** Try hard to create a new entry - we want the IP address to appear in
- the cache (even if this means removing an active entry or so). */
- #define ETHARP_FLAG_TRY_HARD 1
- #define ETHARP_FLAG_FIND_ONLY 2
- #define ETHARP_FLAG_STATIC_ENTRY 4
- #if LWIP_NETIF_HWADDRHINT
- #define ETHARP_SET_HINT(netif, hint) if (((netif) != NULL) && ((netif)->addr_hint != NULL)) \
- *((netif)->addr_hint) = (hint);
- #else /* LWIP_NETIF_HWADDRHINT */
- #define ETHARP_SET_HINT(netif, hint) (etharp_cached_entry = (hint))
- #endif /* LWIP_NETIF_HWADDRHINT */
- static err_t update_arp_entry(struct netif *netif, ip_addr_t *ipaddr, struct eth_addr *ethaddr, u8_t flags);
- /* Some checks, instead of etharp_init(): */
- #if (LWIP_ARP && (ARP_TABLE_SIZE > 0x7f))
- #error "ARP_TABLE_SIZE must fit in an s8_t, you have to reduce it in your lwipopts.h"
- #endif
- #if ARP_QUEUEING
- /**
- * Free a complete queue of etharp entries
- *
- * @param q a qeueue of etharp_q_entry's to free
- */
- static void
- free_etharp_q(struct etharp_q_entry *q)
- {
- struct etharp_q_entry *r;
- LWIP_ASSERT("q != NULL", q != NULL);
- LWIP_ASSERT("q->p != NULL", q->p != NULL);
- while (q) {
- r = q;
- q = q->next;
- LWIP_ASSERT("r->p != NULL", (r->p != NULL));
- pbuf_free(r->p);
- memp_free(MEMP_ARP_QUEUE, r);
- }
- }
- #else /* ARP_QUEUEING */
- /** Compatibility define: free the queued pbuf */
- #define free_etharp_q(q) pbuf_free(q)
- #endif /* ARP_QUEUEING */
- /** Clean up ARP table entries */
- static void ICACHE_FLASH_ATTR
- free_entry(int i)
- {
- /* remove from SNMP ARP index tree */
- snmp_delete_arpidx_tree(arp_table[i].netif, &arp_table[i].ipaddr);
- /* and empty packet queue */
- if (arp_table[i].q != NULL) {
- /* remove all queued packets */
- LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: freeing entry %"U16_F", packet queue %p.\n", (u16_t)i, (void *)(arp_table[i].q)));
- free_etharp_q(arp_table[i].q);
- arp_table[i].q = NULL;
- }
- /* recycle entry for re-use */
- arp_table[i].state = ETHARP_STATE_EMPTY;
- #if ETHARP_SUPPORT_STATIC_ENTRIES
- arp_table[i].static_entry = 0;
- #endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
- #ifdef LWIP_DEBUG
- /* for debugging, clean out the complete entry */
- arp_table[i].ctime = 0;
- #if LWIP_SNMP
- arp_table[i].netif = NULL;
- #endif /* LWIP_SNMP */
- ip_addr_set_zero(&arp_table[i].ipaddr);
- arp_table[i].ethaddr = ethzero;
- #endif /* LWIP_DEBUG */
- }
- /**
- * Clears expired entries in the ARP table.
- *
- * This function should be called every ETHARP_TMR_INTERVAL milliseconds (5 seconds),
- * in order to expire entries in the ARP table.
- */
- void
- etharp_tmr(void)
- {
- u8_t i;
- LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer\n"));
- /* remove expired entries from the ARP table */
- for (i = 0; i < ARP_TABLE_SIZE; ++i) {
- u8_t state = arp_table[i].state;
- if (state != ETHARP_STATE_EMPTY
- #if ETHARP_SUPPORT_STATIC_ENTRIES
- && (arp_table[i].static_entry == 0)
- #endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
- ) {
- arp_table[i].ctime++;
- if ((arp_table[i].ctime >= ARP_MAXAGE) ||
- ((arp_table[i].state == ETHARP_STATE_PENDING) &&
- (arp_table[i].ctime >= ARP_MAXPENDING))) {
- /* pending or stable entry has become old! */
- LWIP_DEBUGF(ETHARP_DEBUG, ("etharp_timer: expired %s entry %"U16_F".\n",
- arp_table[i].state >= ETHARP_STATE_STABLE ? "stable" : "pending", (u16_t)i));
- /* clean up entries that have just been expired */
- free_entry(i);
- }
- else if (arp_table[i].state == ETHARP_STATE_STABLE_REREQUESTING) {
- /* Reset state to stable, so that the next transmitted packet will
- re-send an ARP request. */
- arp_table[i].state = ETHARP_STATE_STABLE;
- }
- #if ARP_QUEUEING
- /* still pending entry? (not expired) */
- if (arp_table[i].state == ETHARP_STATE_PENDING) {
- /* resend an ARP query here? */
- }
- #endif /* ARP_QUEUEING */
- }
- }
- }
- /**
- * Search the ARP table for a matching or new entry.
- *
- * If an IP address is given, return a pending or stable ARP entry that matches
- * the address. If no match is found, create a new entry with this address set,
- * but in state ETHARP_EMPTY. The caller must check and possibly change the
- * state of the returned entry.
- *
- * If ipaddr is NULL, return a initialized new entry in state ETHARP_EMPTY.
- *
- * In all cases, attempt to create new entries from an empty entry. If no
- * empty entries are available and ETHARP_FLAG_TRY_HARD flag is set, recycle
- * old entries. Heuristic choose the least important entry for recycling.
- *
- * @param ipaddr IP address to find in ARP cache, or to add if not found.
- * @param flags @see definition of ETHARP_FLAG_*
- * @param netif netif related to this address (used for NETIF_HWADDRHINT)
- *
- * @return The ARP entry index that matched or is created, ERR_MEM if no
- * entry is found or could be recycled.
- */
- static s8_t ICACHE_FLASH_ATTR
- find_entry(ip_addr_t *ipaddr, u8_t flags)
- {
- s8_t old_pending = ARP_TABLE_SIZE, old_stable = ARP_TABLE_SIZE;
- s8_t empty = ARP_TABLE_SIZE;
- u8_t i = 0, age_pending = 0, age_stable = 0;
- /* oldest entry with packets on queue */
- s8_t old_queue = ARP_TABLE_SIZE;
- /* its age */
- u8_t age_queue = 0;
- /**
- * a) do a search through the cache, remember candidates
- * b) select candidate entry
- * c) create new entry
- */
- /* a) in a single search sweep, do all of this
- * 1) remember the first empty entry (if any)
- * 2) remember the oldest stable entry (if any)
- * 3) remember the oldest pending entry without queued packets (if any)
- * 4) remember the oldest pending entry with queued packets (if any)
- * 5) search for a matching IP entry, either pending or stable
- * until 5 matches, or all entries are searched for.
- */
- for (i = 0; i < ARP_TABLE_SIZE; ++i) {
- u8_t state = arp_table[i].state;
- /* no empty entry found yet and now we do find one? */
- if ((empty == ARP_TABLE_SIZE) && (state == ETHARP_STATE_EMPTY)) {
- LWIP_DEBUGF(ETHARP_DEBUG, ("find_entry: found empty entry %"U16_F"\n", (u16_t)i));
- /* remember first empty entry */
- empty = i;
- } else if (state != ETHARP_STATE_EMPTY) {
- LWIP_ASSERT("state == ETHARP_STATE_PENDING || state >= ETHARP_STATE_STABLE",
- state == ETHARP_STATE_PENDING || state >= ETHARP_STATE_STABLE);
- /* if given, does IP address match IP address in ARP entry? */
- if (ipaddr && ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: found matching entry %"U16_F"\n", (u16_t)i));
- /* found exact IP address match, simply bail out */
- return i;
- }
- /* pending entry? */
- if (state == ETHARP_STATE_PENDING) {
- /* pending with queued packets? */
- if (arp_table[i].q != NULL) {
- if (arp_table[i].ctime >= age_queue) {
- old_queue = i;
- age_queue = arp_table[i].ctime;
- }
- } else
- /* pending without queued packets? */
- {
- if (arp_table[i].ctime >= age_pending) {
- old_pending = i;
- age_pending = arp_table[i].ctime;
- }
- }
- /* stable entry? */
- } else if (state >= ETHARP_STATE_STABLE) {
- #if ETHARP_SUPPORT_STATIC_ENTRIES
- /* don't record old_stable for static entries since they never expire */
- if (arp_table[i].static_entry == 0)
- #endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
- {
- /* remember entry with oldest stable entry in oldest, its age in maxtime */
- if (arp_table[i].ctime >= age_stable) {
- old_stable = i;
- age_stable = arp_table[i].ctime;
- }
- }
- }
- }
- }
- /* { we have no match } => try to create a new entry */
- /* don't create new entry, only search? */
- if (((flags & ETHARP_FLAG_FIND_ONLY) != 0) ||
- /* or no empty entry found and not allowed to recycle? */
- ((empty == ARP_TABLE_SIZE) && ((flags & ETHARP_FLAG_TRY_HARD) == 0))) {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: no empty entry found and not allowed to recycle\n"));
- return (s8_t)ERR_MEM;
- }
- /* b) choose the least destructive entry to recycle:
- * 1) empty entry
- * 2) oldest stable entry
- * 3) oldest pending entry without queued packets
- * 4) oldest pending entry with queued packets
- *
- * { ETHARP_FLAG_TRY_HARD is set at this point }
- */
- /* 1) empty entry available? */
- if (empty < ARP_TABLE_SIZE) {
- i = empty;
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: selecting empty entry %"U16_F"\n", (u16_t)i));
- } else {
- /* 2) found recyclable stable entry? */
- if (old_stable < ARP_TABLE_SIZE) {
- /* recycle oldest stable*/
- i = old_stable;
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: selecting oldest stable entry %"U16_F"\n", (u16_t)i));
- /* no queued packets should exist on stable entries */
- LWIP_ASSERT("arp_table[i].q == NULL", arp_table[i].q == NULL);
- /* 3) found recyclable pending entry without queued packets? */
- } else if (old_pending < ARP_TABLE_SIZE) {
- /* recycle oldest pending */
- i = old_pending;
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: selecting oldest pending entry %"U16_F" (without queue)\n", (u16_t)i));
- /* 4) found recyclable pending entry with queued packets? */
- } else if (old_queue < ARP_TABLE_SIZE) {
- /* recycle oldest pending (queued packets are free in free_entry) */
- i = old_queue;
- 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)));
- /* no empty or recyclable entries found */
- } else {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("find_entry: no empty or recyclable entries found\n"));
- return (s8_t)ERR_MEM;
- }
- /* { empty or recyclable entry found } */
- LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
- free_entry(i);
- }
- LWIP_ASSERT("i < ARP_TABLE_SIZE", i < ARP_TABLE_SIZE);
- LWIP_ASSERT("arp_table[i].state == ETHARP_STATE_EMPTY",
- arp_table[i].state == ETHARP_STATE_EMPTY);
- /* IP address given? */
- if (ipaddr != NULL) {
- /* set IP address */
- ip_addr_copy(arp_table[i].ipaddr, *ipaddr);
- }
- arp_table[i].ctime = 0;
- #if ETHARP_SUPPORT_STATIC_ENTRIES
- arp_table[i].static_entry = 0;
- #endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
- return (err_t)i;
- }
- /**
- * Send an IP packet on the network using netif->linkoutput
- * The ethernet header is filled in before sending.
- *
- * @params netif the lwIP network interface on which to send the packet
- * @params p the packet to send, p->payload pointing to the (uninitialized) ethernet header
- * @params src the source MAC address to be copied into the ethernet header
- * @params dst the destination MAC address to be copied into the ethernet header
- * @return ERR_OK if the packet was sent, any other err_t on failure
- */
- static err_t ICACHE_FLASH_ATTR
- etharp_send_ip(struct netif *netif, struct pbuf *p, struct eth_addr *src, struct eth_addr *dst)
- {
- struct eth_hdr *ethhdr = (struct eth_hdr *)p->payload;
- LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
- (netif->hwaddr_len == ETHARP_HWADDR_LEN));
- ETHADDR32_COPY(ðhdr->dest, dst);
- ETHADDR16_COPY(ðhdr->src, src);
- ethhdr->type = PP_HTONS(ETHTYPE_IP);
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_send_ip: sending packet %p\n", (void *)p));
- /* send the packet */
- return netif->linkoutput(netif, p);
- }
- /**
- * Update (or insert) a IP/MAC address pair in the ARP cache.
- *
- * If a pending entry is resolved, any queued packets will be sent
- * at this point.
- *
- * @param netif netif related to this entry (used for NETIF_ADDRHINT)
- * @param ipaddr IP address of the inserted ARP entry.
- * @param ethaddr Ethernet address of the inserted ARP entry.
- * @param flags @see definition of ETHARP_FLAG_*
- *
- * @return
- * - ERR_OK Succesfully updated ARP cache.
- * - ERR_MEM If we could not add a new ARP entry when ETHARP_FLAG_TRY_HARD was set.
- * - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
- *
- * @see pbuf_free()
- */
- static err_t ICACHE_FLASH_ATTR
- update_arp_entry(struct netif *netif, ip_addr_t *ipaddr, struct eth_addr *ethaddr, u8_t flags)
- {
- s8_t i;
- LWIP_ASSERT("netif->hwaddr_len == ETHARP_HWADDR_LEN", netif->hwaddr_len == ETHARP_HWADDR_LEN);
- 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",
- ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
- ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
- ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
- /* non-unicast address? */
- if (ip_addr_isany(ipaddr) ||
- ip_addr_isbroadcast(ipaddr, netif) ||
- ip_addr_ismulticast(ipaddr)) {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("update_arp_entry: will not add non-unicast IP address to ARP cache\n"));
- return ERR_ARG;
- }
- /* find or create ARP entry */
- i = find_entry(ipaddr, flags);
- /* bail out if no entry could be found */
- if (i < 0) {
- return (err_t)i;
- }
- #if ETHARP_SUPPORT_STATIC_ENTRIES
- if (flags & ETHARP_FLAG_STATIC_ENTRY) {
- /* record static type */
- arp_table[i].static_entry = 1;
- }
- #endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
- /* mark it stable */
- arp_table[i].state = ETHARP_STATE_STABLE;
- #if LWIP_SNMP
- /* record network interface */
- arp_table[i].netif = netif;
- #endif /* LWIP_SNMP */
- /* insert in SNMP ARP index tree */
- snmp_insert_arpidx_tree(netif, &arp_table[i].ipaddr);
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("update_arp_entry: updating stable entry %"S16_F"\n", (s16_t)i));
- /* update address */
- ETHADDR32_COPY(&arp_table[i].ethaddr, ethaddr);
- /* reset time stamp */
- arp_table[i].ctime = 0;
- /* this is where we will send out queued packets! */
- #if ARP_QUEUEING
- while (arp_table[i].q != NULL) {
- struct pbuf *p;
- /* remember remainder of queue */
- struct etharp_q_entry *q = arp_table[i].q;
- /* pop first item off the queue */
- arp_table[i].q = q->next;
- /* get the packet pointer */
- p = q->p;
- /* now queue entry can be freed */
- memp_free(MEMP_ARP_QUEUE, q);
- #else /* ARP_QUEUEING */
- if (arp_table[i].q != NULL) {
- struct pbuf *p = arp_table[i].q;
- arp_table[i].q = NULL;
- #endif /* ARP_QUEUEING */
- /* send the queued IP packet */
- etharp_send_ip(netif, p, (struct eth_addr*)(netif->hwaddr), ethaddr);
- /* free the queued IP packet */
- pbuf_free(p);
- }
- return ERR_OK;
- }
- #if ETHARP_SUPPORT_STATIC_ENTRIES
- /** Add a new static entry to the ARP table. If an entry exists for the
- * specified IP address, this entry is overwritten.
- * If packets are queued for the specified IP address, they are sent out.
- *
- * @param ipaddr IP address for the new static entry
- * @param ethaddr ethernet address for the new static entry
- * @return @see return values of etharp_add_static_entry
- */
- err_t
- etharp_add_static_entry(ip_addr_t *ipaddr, struct eth_addr *ethaddr)
- {
- struct netif *netif;
- 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",
- ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr),
- ethaddr->addr[0], ethaddr->addr[1], ethaddr->addr[2],
- ethaddr->addr[3], ethaddr->addr[4], ethaddr->addr[5]));
- netif = ip_route(ipaddr);
- if (netif == NULL) {
- return ERR_RTE;
- }
- return update_arp_entry(netif, ipaddr, ethaddr, ETHARP_FLAG_TRY_HARD | ETHARP_FLAG_STATIC_ENTRY);
- }
- /** Remove a static entry from the ARP table previously added with a call to
- * etharp_add_static_entry.
- *
- * @param ipaddr IP address of the static entry to remove
- * @return ERR_OK: entry removed
- * ERR_MEM: entry wasn't found
- * ERR_ARG: entry wasn't a static entry but a dynamic one
- */
- err_t
- etharp_remove_static_entry(ip_addr_t *ipaddr)
- {
- s8_t i;
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_remove_static_entry: %"U16_F".%"U16_F".%"U16_F".%"U16_F"\n",
- ip4_addr1_16(ipaddr), ip4_addr2_16(ipaddr), ip4_addr3_16(ipaddr), ip4_addr4_16(ipaddr)));
- /* find or create ARP entry */
- i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
- /* bail out if no entry could be found */
- if (i < 0) {
- return (err_t)i;
- }
- if ((arp_table[i].state != ETHARP_STATE_STABLE) ||
- (arp_table[i].static_entry == 0)) {
- /* entry wasn't a static entry, cannot remove it */
- return ERR_ARG;
- }
- /* entry found, free it */
- free_entry(i);
- return ERR_OK;
- }
- #endif /* ETHARP_SUPPORT_STATIC_ENTRIES */
- /**
- * Remove all ARP table entries of the specified netif.
- *
- * @param netif points to a network interface
- */
- void ICACHE_FLASH_ATTR etharp_cleanup_netif(struct netif *netif)
- {
- u8_t i;
- for (i = 0; i < ARP_TABLE_SIZE; ++i) {
- u8_t state = arp_table[i].state;
- if ((state != ETHARP_STATE_EMPTY) && (arp_table[i].netif == netif)) {
- free_entry(i);
- }
- }
- }
- /**
- * Finds (stable) ethernet/IP address pair from ARP table
- * using interface and IP address index.
- * @note the addresses in the ARP table are in network order!
- *
- * @param netif points to interface index
- * @param ipaddr points to the (network order) IP address index
- * @param eth_ret points to return pointer
- * @param ip_ret points to return pointer
- * @return table index if found, -1 otherwise
- */
- s8_t
- etharp_find_addr(struct netif *netif, ip_addr_t *ipaddr,
- struct eth_addr **eth_ret, ip_addr_t **ip_ret)
- {
- s8_t i;
- LWIP_ASSERT("eth_ret != NULL && ip_ret != NULL",
- eth_ret != NULL && ip_ret != NULL);
- LWIP_UNUSED_ARG(netif);
- i = find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY);
- if((i >= 0) && (arp_table[i].state >= ETHARP_STATE_STABLE)) {
- *eth_ret = &arp_table[i].ethaddr;
- *ip_ret = &arp_table[i].ipaddr;
- return i;
- }
- return -1;
- }
- #if ETHARP_TRUST_IP_MAC
- /**
- * Updates the ARP table using the given IP packet.
- *
- * Uses the incoming IP packet's source address to update the
- * ARP cache for the local network. The function does not alter
- * or free the packet. This function must be called before the
- * packet p is passed to the IP layer.
- *
- * @param netif The lwIP network interface on which the IP packet pbuf arrived.
- * @param p The IP packet that arrived on netif.
- *
- * @return NULL
- *
- * @see pbuf_free()
- */
- static void ICACHE_FLASH_ATTR
- etharp_ip_input(struct netif *netif, struct pbuf *p)
- {
- struct eth_hdr *ethhdr;
- struct ip_hdr *iphdr;
- ip_addr_t iphdr_src;
- LWIP_ERROR("netif != NULL", (netif != NULL), return;);
- /* Only insert an entry if the source IP address of the
- incoming IP packet comes from a host on the local network. */
- ethhdr = (struct eth_hdr *)p->payload;
- iphdr = (struct ip_hdr *)((u8_t*)ethhdr + SIZEOF_ETH_HDR);
- #if ETHARP_SUPPORT_VLAN
- if (ethhdr->type == ETHTYPE_VLAN) {
- iphdr = (struct ip_hdr *)((u8_t*)ethhdr + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
- }
- #endif /* ETHARP_SUPPORT_VLAN */
- ip_addr_copy(iphdr_src, iphdr->src);
- /* source is not on the local network? */
- if (!ip_addr_netcmp(&iphdr_src, &(netif->ip_addr), &(netif->netmask))) {
- /* do nothing */
- return;
- }
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_ip_input: updating ETHARP table.\n"));
- /* update the source IP address in the cache, if present */
- /* @todo We could use ETHARP_FLAG_TRY_HARD if we think we are going to talk
- * back soon (for example, if the destination IP address is ours. */
- update_arp_entry(netif, &iphdr_src, &(ethhdr->src), ETHARP_FLAG_FIND_ONLY);
- }
- #endif /* ETHARP_TRUST_IP_MAC */
- /**
- * Responds to ARP requests to us. Upon ARP replies to us, add entry to cache
- * send out queued IP packets. Updates cache with snooped address pairs.
- *
- * Should be called for incoming ARP packets. The pbuf in the argument
- * is freed by this function.
- *
- * @param netif The lwIP network interface on which the ARP packet pbuf arrived.
- * @param ethaddr Ethernet address of netif.
- * @param p The ARP packet that arrived on netif. Is freed by this function.
- *
- * @return NULL
- *
- * @see pbuf_free()
- */
- static void ICACHE_FLASH_ATTR
- etharp_arp_input(struct netif *netif, struct eth_addr *ethaddr, struct pbuf *p)
- {
- struct etharp_hdr *hdr;
- struct eth_hdr *ethhdr;
- /* these are aligned properly, whereas the ARP header fields might not be */
- ip_addr_t sipaddr, dipaddr;
- u8_t for_us;
- #if LWIP_AUTOIP
- const u8_t * ethdst_hwaddr;
- #endif /* LWIP_AUTOIP */
- #ifdef EBUF_LWIP
- struct pbuf *q;
- #endif /* EBUF_LWIP */
- LWIP_ERROR("netif != NULL", (netif != NULL), return;);
- /* drop short ARP packets: we have to check for p->len instead of p->tot_len here
- since a struct etharp_hdr is pointed to p->payload, so it musn't be chained! */
- if (p->len < SIZEOF_ETHARP_PACKET) {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING,
- ("etharp_arp_input: packet dropped, too short (%"S16_F"/%"S16_F")\n", p->tot_len,
- (s16_t)SIZEOF_ETHARP_PACKET));
- ETHARP_STATS_INC(etharp.lenerr);
- ETHARP_STATS_INC(etharp.drop);
- pbuf_free(p);
- return;
- }
- ethhdr = (struct eth_hdr *)p->payload;
- hdr = (struct etharp_hdr *)((u8_t*)ethhdr + SIZEOF_ETH_HDR);
- #if ETHARP_SUPPORT_VLAN
- if (ethhdr->type == ETHTYPE_VLAN) {
- hdr = (struct etharp_hdr *)(((u8_t*)ethhdr) + SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR);
- }
- #endif /* ETHARP_SUPPORT_VLAN */
- /* RFC 826 "Packet Reception": */
- if ((hdr->hwtype != PP_HTONS(HWTYPE_ETHERNET)) ||
- (hdr->hwlen != ETHARP_HWADDR_LEN) ||
- (hdr->protolen != sizeof(ip_addr_t)) ||
- (hdr->proto != PP_HTONS(ETHTYPE_IP)) ||
- (ethhdr->type != PP_HTONS(ETHTYPE_ARP))) {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_WARNING,
- ("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",
- hdr->hwtype, hdr->hwlen, hdr->proto, hdr->protolen, ethhdr->type));
- ETHARP_STATS_INC(etharp.proterr);
- ETHARP_STATS_INC(etharp.drop);
- pbuf_free(p);
- return;
- }
- ETHARP_STATS_INC(etharp.recv);
- #if LWIP_AUTOIP
- /* We have to check if a host already has configured our random
- * created link local address and continously check if there is
- * a host with this IP-address so we can detect collisions */
- autoip_arp_reply(netif, hdr);
- #endif /* LWIP_AUTOIP */
- /* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
- * structure packing (not using structure copy which breaks strict-aliasing rules). */
- IPADDR2_COPY(&sipaddr, &hdr->sipaddr);
- IPADDR2_COPY(&dipaddr, &hdr->dipaddr);
- /* this interface is not configured? */
- if (ip_addr_isany(&netif->ip_addr)) {
- for_us = 0;
- } else {
- /* ARP packet directed to us? */
- for_us = (u8_t)ip_addr_cmp(&dipaddr, &(netif->ip_addr));
- }
- /* ARP message directed to us?
- -> add IP address in ARP cache; assume requester wants to talk to us,
- can result in directly sending the queued packets for this host.
- ARP message not directed to us?
- -> update the source IP address in the cache, if present */
- update_arp_entry(netif, &sipaddr, &(hdr->shwaddr),
- for_us ? ETHARP_FLAG_TRY_HARD : ETHARP_FLAG_FIND_ONLY);
- /* now act on the message itself */
- switch (hdr->opcode) {
- /* ARP request? */
- case PP_HTONS(ARP_REQUEST):
- /* ARP request. If it asked for our address, we send out a
- * reply. In any case, we time-stamp any existing ARP entry,
- * and possiby send out an IP packet that was queued on it. */
- LWIP_DEBUGF (ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP request\n"));
- /* ARP request for our address? */
- if (for_us) {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_arp_input: replying to ARP request for our IP address\n"));
- /* Re-use pbuf to send ARP reply.
- Since we are re-using an existing pbuf, we can't call etharp_raw since
- that would allocate a new pbuf. */
- hdr->opcode = htons(ARP_REPLY);
- IPADDR2_COPY(&hdr->dipaddr, &hdr->sipaddr);
- IPADDR2_COPY(&hdr->sipaddr, &netif->ip_addr);
- LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
- (netif->hwaddr_len == ETHARP_HWADDR_LEN));
- #if LWIP_AUTOIP
- /* If we are using Link-Local, all ARP packets that contain a Link-Local
- * 'sender IP address' MUST be sent using link-layer broadcast instead of
- * link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
- ethdst_hwaddr = ip_addr_islinklocal(&netif->ip_addr) ? (u8_t*)(ethbroadcast.addr) : hdr->shwaddr.addr;
- #endif /* LWIP_AUTOIP */
- ETHADDR16_COPY(&hdr->dhwaddr, &hdr->shwaddr);
- #if LWIP_AUTOIP
- ETHADDR16_COPY(ðhdr->dest, ethdst_hwaddr);
- #else /* LWIP_AUTOIP */
- ETHADDR16_COPY(ðhdr->dest, &hdr->shwaddr);
- #endif /* LWIP_AUTOIP */
- ETHADDR16_COPY(&hdr->shwaddr, ethaddr);
- ETHADDR16_COPY(ðhdr->src, ethaddr);
- /* hwtype, hwaddr_len, proto, protolen and the type in the ethernet header
- are already correct, we tested that before */
- #ifdef EBUF_LWIP
- /*
- * don't do flip-flop here... do a copy here.
- * otherwise, we need to handle existing pbuf->eb in ieee80211_output.c
- */
- q = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
- if (q != NULL) {
- pbuf_copy(q, p);
- //pbuf_free(p);
- } else {
- LWIP_ASSERT("q != NULL", q != NULL);
- }
- netif->linkoutput(netif, q);
- pbuf_free(q);
- #else
- /* return ARP reply */
- netif->linkoutput(netif, p);
- #endif /* ESF_LWIP */
- /* we are not configured? */
- } else if (ip_addr_isany(&netif->ip_addr)) {
- /* { for_us == 0 and netif->ip_addr.addr == 0 } */
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_arp_input: we are unconfigured, ARP request ignored.\n"));
- /* request was not directed to us */
- } else {
- /* { for_us == 0 and netif->ip_addr.addr != 0 } */
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_arp_input: ARP request was not for us.\n"));
- }
- break;
- case PP_HTONS(ARP_REPLY):
- /* ARP reply. We already updated the ARP cache earlier. */
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_arp_input: incoming ARP reply\n"));
- #if (LWIP_DHCP && DHCP_DOES_ARP_CHECK)
- /* DHCP wants to know about ARP replies from any host with an
- * IP address also offered to us by the DHCP server. We do not
- * want to take a duplicate IP address on a single network.
- * @todo How should we handle redundant (fail-over) interfaces? */
- dhcp_arp_reply(netif, &sipaddr);
- #endif /* (LWIP_DHCP && DHCP_DOES_ARP_CHECK) */
- break;
- default:
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_arp_input: ARP unknown opcode type %"S16_F"\n", htons(hdr->opcode)));
- ETHARP_STATS_INC(etharp.err);
- break;
- }
- /* free ARP packet */
- pbuf_free(p);
- }
- /** Just a small helper function that sends a pbuf to an ethernet address
- * in the arp_table specified by the index 'arp_idx'.
- */
- static err_t ICACHE_FLASH_ATTR
- etharp_output_to_arp_index(struct netif *netif, struct pbuf *q, u8_t arp_idx)
- {
- LWIP_ASSERT("arp_table[arp_idx].state >= ETHARP_STATE_STABLE",
- arp_table[arp_idx].state >= ETHARP_STATE_STABLE);
- /* if arp table entry is about to expire: re-request it,
- but only if its state is ETHARP_STATE_STABLE to prevent flooding the
- network with ARP requests if this address is used frequently. */
- if ((arp_table[arp_idx].state == ETHARP_STATE_STABLE) &&
- (arp_table[arp_idx].ctime >= ARP_AGE_REREQUEST_USED)) {
- if (etharp_request(netif, &arp_table[arp_idx].ipaddr) == ERR_OK) {
- arp_table[arp_idx].state = ETHARP_STATE_STABLE_REREQUESTING;
- }
- }
- return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr),
- &arp_table[arp_idx].ethaddr);
- }
- /**
- * Resolve and fill-in Ethernet address header for outgoing IP packet.
- *
- * For IP multicast and broadcast, corresponding Ethernet addresses
- * are selected and the packet is transmitted on the link.
- *
- * For unicast addresses, the packet is submitted to etharp_query(). In
- * case the IP address is outside the local network, the IP address of
- * the gateway is used.
- *
- * @param netif The lwIP network interface which the IP packet will be sent on.
- * @param q The pbuf(s) containing the IP packet to be sent.
- * @param ipaddr The IP address of the packet destination.
- *
- * @return
- * - ERR_RTE No route to destination (no gateway to external networks),
- * or the return type of either etharp_query() or etharp_send_ip().
- */
- err_t
- etharp_output(struct netif *netif, struct pbuf *q, ip_addr_t *ipaddr)
- {
- struct eth_addr *dest, mcastaddr;
- /* make room for Ethernet header - should not fail */
- if (pbuf_header(q, sizeof(struct eth_hdr)) != 0) {
- /* bail out */
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS,
- ("etharp_output: could not allocate room for header.\n"));
- LINK_STATS_INC(link.lenerr);
- return ERR_BUF;
- }
- /* assume unresolved Ethernet address */
- dest = NULL;
- /* Determine on destination hardware address. Broadcasts and multicasts
- * are special, other IP addresses are looked up in the ARP table. */
- /* broadcast destination IP address? */
- if (ip_addr_isbroadcast(ipaddr, netif)) {
- /* broadcast on Ethernet also */
- dest = (struct eth_addr *)ðbroadcast;
- /* multicast destination IP address? */
- } else if (ip_addr_ismulticast(ipaddr)) {
- /* Hash IP multicast address to MAC address.*/
- mcastaddr.addr[0] = 0x01;
- mcastaddr.addr[1] = 0x00;
- mcastaddr.addr[2] = 0x5e;
- mcastaddr.addr[3] = ip4_addr2(ipaddr) & 0x7f;
- mcastaddr.addr[4] = ip4_addr3(ipaddr);
- mcastaddr.addr[5] = ip4_addr4(ipaddr);
- /* destination Ethernet address is multicast */
- dest = &mcastaddr;
- /* unicast destination IP address? */
- } else {
- s8_t i;
- /* outside local network? if so, this can neither be a global broadcast nor
- a subnet broadcast. */
- if (!ip_addr_netcmp(ipaddr, &(netif->ip_addr), &(netif->netmask)) &&
- !ip_addr_islinklocal(ipaddr)) {
- #if LWIP_AUTOIP
- struct ip_hdr *iphdr = (struct ip_hdr*)((u8_t*)q->payload +
- sizeof(struct eth_hdr));
- /* According to RFC 3297, chapter 2.6.2 (Forwarding Rules), a packet with
- a link-local source address must always be "directly to its destination
- on the same physical link. The host MUST NOT send the packet to any
- router for forwarding". */
- if (!ip_addr_islinklocal(&iphdr->src))
- #endif /* LWIP_AUTOIP */
- {
- /* interface has default gateway? */
- if (!ip_addr_isany(&netif->gw)) {
- /* send to hardware address of default gateway IP address */
- ipaddr = &(netif->gw);
- /* no default gateway available */
- } else {
- /* no route to destination error (default gateway missing) */
- return ERR_RTE;
- }
- }
- }
- #if LWIP_NETIF_HWADDRHINT
- if (netif->addr_hint != NULL) {
- /* per-pcb cached entry was given */
- u8_t etharp_cached_entry = *(netif->addr_hint);
- if (etharp_cached_entry < ARP_TABLE_SIZE) {
- #endif /* LWIP_NETIF_HWADDRHINT */
- if ((arp_table[etharp_cached_entry].state >= ETHARP_STATE_STABLE) &&
- (ip_addr_cmp(ipaddr, &arp_table[etharp_cached_entry].ipaddr))) {
- /* the per-pcb-cached entry is stable and the right one! */
- ETHARP_STATS_INC(etharp.cachehit);
- return etharp_output_to_arp_index(netif, q, etharp_cached_entry);
- }
- #if LWIP_NETIF_HWADDRHINT
- }
- }
- #endif /* LWIP_NETIF_HWADDRHINT */
- /* find stable entry: do this here since this is a critical path for
- throughput and etharp_find_entry() is kind of slow */
- for (i = 0; i < ARP_TABLE_SIZE; i++) {
- if ((arp_table[i].state >= ETHARP_STATE_STABLE) &&
- (ip_addr_cmp(ipaddr, &arp_table[i].ipaddr))) {
- /* found an existing, stable entry */
- ETHARP_SET_HINT(netif, i);
- return etharp_output_to_arp_index(netif, q, i);
- }
- }
- /* queue on destination Ethernet address belonging to ipaddr */
- return etharp_query(netif, ipaddr, q);
- }
- /* continuation for multicast/broadcast destinations */
- /* obtain source Ethernet address of the given interface */
- /* send packet directly on the link */
- return etharp_send_ip(netif, q, (struct eth_addr*)(netif->hwaddr), dest);
- }
- /**
- * Send an ARP request for the given IP address and/or queue a packet.
- *
- * If the IP address was not yet in the cache, a pending ARP cache entry
- * is added and an ARP request is sent for the given address. The packet
- * is queued on this entry.
- *
- * If the IP address was already pending in the cache, a new ARP request
- * is sent for the given address. The packet is queued on this entry.
- *
- * If the IP address was already stable in the cache, and a packet is
- * given, it is directly sent and no ARP request is sent out.
- *
- * If the IP address was already stable in the cache, and no packet is
- * given, an ARP request is sent out.
- *
- * @param netif The lwIP network interface on which ipaddr
- * must be queried for.
- * @param ipaddr The IP address to be resolved.
- * @param q If non-NULL, a pbuf that must be delivered to the IP address.
- * q is not freed by this function.
- *
- * @note q must only be ONE packet, not a packet queue!
- *
- * @return
- * - ERR_BUF Could not make room for Ethernet header.
- * - ERR_MEM Hardware address unknown, and no more ARP entries available
- * to query for address or queue the packet.
- * - ERR_MEM Could not queue packet due to memory shortage.
- * - ERR_RTE No route to destination (no gateway to external networks).
- * - ERR_ARG Non-unicast address given, those will not appear in ARP cache.
- *
- */
- err_t
- etharp_query(struct netif *netif, ip_addr_t *ipaddr, struct pbuf *q)
- {
- struct eth_addr * srcaddr = (struct eth_addr *)netif->hwaddr;
- err_t result = ERR_MEM;
- s8_t i; /* ARP entry index */
- /* non-unicast address? */
- if (ip_addr_isbroadcast(ipaddr, netif) ||
- ip_addr_ismulticast(ipaddr) ||
- ip_addr_isany(ipaddr)) {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: will not add non-unicast IP address to ARP cache\n"));
- return ERR_ARG;
- }
- /* find entry in ARP cache, ask to create entry if queueing packet */
- i = find_entry(ipaddr, ETHARP_FLAG_TRY_HARD);
- /* could not find or create entry? */
- if (i < 0) {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: could not create ARP entry\n"));
- if (q) {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: packet dropped\n"));
- ETHARP_STATS_INC(etharp.memerr);
- }
- return (err_t)i;
- }
- /* mark a fresh entry as pending (we just sent a request) */
- if (arp_table[i].state == ETHARP_STATE_EMPTY) {
- arp_table[i].state = ETHARP_STATE_PENDING;
- }
- /* { i is either a STABLE or (new or existing) PENDING entry } */
- LWIP_ASSERT("arp_table[i].state == PENDING or STABLE",
- ((arp_table[i].state == ETHARP_STATE_PENDING) ||
- (arp_table[i].state >= ETHARP_STATE_STABLE)));
- /* do we have a pending entry? or an implicit query request? */
- if ((arp_table[i].state == ETHARP_STATE_PENDING) || (q == NULL)) {
- /* try to resolve it; send out ARP request */
- result = etharp_request(netif, ipaddr);
- if (result != ERR_OK) {
- /* ARP request couldn't be sent */
- /* We don't re-send arp request in etharp_tmr, but we still queue packets,
- since this failure could be temporary, and the next packet calling
- etharp_query again could lead to sending the queued packets. */
- }
- if (q == NULL) {
- return result;
- }
- }
- /* packet given? */
- LWIP_ASSERT("q != NULL", q != NULL);
- /* stable entry? */
- if (arp_table[i].state >= ETHARP_STATE_STABLE) {
- /* we have a valid IP->Ethernet address mapping */
- ETHARP_SET_HINT(netif, i);
- /* send the packet */
- result = etharp_send_ip(netif, q, srcaddr, &(arp_table[i].ethaddr));
- /* pending entry? (either just created or already pending */
- } else if (arp_table[i].state == ETHARP_STATE_PENDING) {
- /* entry is still pending, queue the given packet 'q' */
- struct pbuf *p;
- int copy_needed = 0;
- /* IF q includes a PBUF_REF, PBUF_POOL or PBUF_RAM, we have no choice but
- * to copy the whole queue into a new PBUF_RAM (see bug #11400)
- * PBUF_ROMs can be left as they are, since ROM must not get changed. */
- p = q;
- while (p) {
- LWIP_ASSERT("no packet queues allowed!", (p->len != p->tot_len) || (p->next == 0));
- if(p->type != PBUF_ROM) {
- copy_needed = 1;
- break;
- }
- p = p->next;
- }
- if(copy_needed) {
- /* copy the whole packet into new pbufs */
- p = pbuf_alloc(PBUF_RAW, p->tot_len, PBUF_RAM);
- if(p != NULL) {
- if (pbuf_copy(p, q) != ERR_OK) {
- pbuf_free(p);
- p = NULL;
- }
- }
- } else {
- /* referencing the old pbuf is enough */
- p = q;
- pbuf_ref(p);
- }
- /* packet could be taken over? */
- if (p != NULL) {
- /* queue packet ... */
- #if ARP_QUEUEING
- struct etharp_q_entry *new_entry;
- /* allocate a new arp queue entry */
- new_entry = (struct etharp_q_entry *)memp_malloc(MEMP_ARP_QUEUE);
- if (new_entry != NULL) {
- unsigned int qlen = 0;
- new_entry->next = 0;
- new_entry->p = p;
- if(arp_table[i].q != NULL) {
- /* queue was already existent, append the new entry to the end */
- struct etharp_q_entry *r;
- r = arp_table[i].q;
- qlen++;
- while (r->next != NULL) {
- r = r->next;
- qlen++;
- }
- r->next = new_entry;
- } else {
- /* queue did not exist, first item in queue */
- arp_table[i].q = new_entry;
- }
- if(qlen >= 3) {
- struct etharp_q_entry *old;
- old = arp_table[i].q;
- arp_table[i].q = arp_table[i].q->next;
- pbuf_free(old->p);
- memp_free(MEM_ARP_QUEUE, old);
- }
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: queued packet %p on ARP entry %"S16_F"\n", (void *)q, (s16_t)i));
- result = ERR_OK;
- } else {
- /* the pool MEMP_ARP_QUEUE is empty */
- pbuf_free(p);
- 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));
- result = ERR_MEM;
- }
- #else /* ARP_QUEUEING */
- /* always queue one packet per ARP request only, freeing a previously queued packet */
- if (arp_table[i].q != NULL) {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: dropped previously queued packet %p for ARP entry %"S16_F"\n", (void *)q, (s16_t)i));
- pbuf_free(arp_table[i].q);
- }
- arp_table[i].q = p;
- result = ERR_OK;
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_query: queued packet %p on ARP entry %"S16_F"\n", (void *)q, (s16_t)i));
- #endif /* ARP_QUEUEING */
- } else {
- ETHARP_STATS_INC(etharp.memerr);
- 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));
- result = ERR_MEM;
- }
- }
- return result;
- }
- /**
- * Send a raw ARP packet (opcode and all addresses can be modified)
- *
- * @param netif the lwip network interface on which to send the ARP packet
- * @param ethsrc_addr the source MAC address for the ethernet header
- * @param ethdst_addr the destination MAC address for the ethernet header
- * @param hwsrc_addr the source MAC address for the ARP protocol header
- * @param ipsrc_addr the source IP address for the ARP protocol header
- * @param hwdst_addr the destination MAC address for the ARP protocol header
- * @param ipdst_addr the destination IP address for the ARP protocol header
- * @param opcode the type of the ARP packet
- * @return ERR_OK if the ARP packet has been sent
- * ERR_MEM if the ARP packet couldn't be allocated
- * any other err_t on failure
- */
- #if !LWIP_AUTOIP
- static
- #endif /* LWIP_AUTOIP */
- err_t ICACHE_FLASH_ATTR
- etharp_raw(struct netif *netif, const struct eth_addr *ethsrc_addr,
- const struct eth_addr *ethdst_addr,
- const struct eth_addr *hwsrc_addr, const ip_addr_t *ipsrc_addr,
- const struct eth_addr *hwdst_addr, const ip_addr_t *ipdst_addr,
- const u16_t opcode)
- {
- struct pbuf *p;
- err_t result = ERR_OK;
- struct eth_hdr *ethhdr;
- struct etharp_hdr *hdr;
- #if LWIP_AUTOIP
- const u8_t * ethdst_hwaddr;
- #endif /* LWIP_AUTOIP */
- /* allocate a pbuf for the outgoing ARP request packet */
- p = pbuf_alloc(PBUF_RAW, SIZEOF_ETHARP_PACKET, PBUF_RAM);
- /* could allocate a pbuf for an ARP request? */
- if (p == NULL) {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE | LWIP_DBG_LEVEL_SERIOUS,
- ("etharp_raw: could not allocate pbuf for ARP request.\n"));
- ETHARP_STATS_INC(etharp.memerr);
- return ERR_MEM;
- }
- LWIP_ASSERT("check that first pbuf can hold struct etharp_hdr",
- (p->len >= SIZEOF_ETHARP_PACKET));
- ethhdr = (struct eth_hdr *)p->payload;
- hdr = (struct etharp_hdr *)((u8_t*)ethhdr + SIZEOF_ETH_HDR);
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_raw: sending raw ARP packet.\n"));
- hdr->opcode = htons(opcode);
- LWIP_ASSERT("netif->hwaddr_len must be the same as ETHARP_HWADDR_LEN for etharp!",
- (netif->hwaddr_len == ETHARP_HWADDR_LEN));
- #if LWIP_AUTOIP
- /* If we are using Link-Local, all ARP packets that contain a Link-Local
- * 'sender IP address' MUST be sent using link-layer broadcast instead of
- * link-layer unicast. (See RFC3927 Section 2.5, last paragraph) */
- ethdst_hwaddr = ip_addr_islinklocal(ipsrc_addr) ? (u8_t*)(ethbroadcast.addr) : ethdst_addr->addr;
- #endif /* LWIP_AUTOIP */
- /* Write the ARP MAC-Addresses */
- ETHADDR16_COPY(&hdr->shwaddr, hwsrc_addr);
- ETHADDR16_COPY(&hdr->dhwaddr, hwdst_addr);
- /* Write the Ethernet MAC-Addresses */
- #if LWIP_AUTOIP
- ETHADDR16_COPY(ðhdr->dest, ethdst_hwaddr);
- #else /* LWIP_AUTOIP */
- ETHADDR16_COPY(ðhdr->dest, ethdst_addr);
- #endif /* LWIP_AUTOIP */
- ETHADDR16_COPY(ðhdr->src, ethsrc_addr);
- /* Copy struct ip_addr2 to aligned ip_addr, to support compilers without
- * structure packing. */
- IPADDR2_COPY(&hdr->sipaddr, ipsrc_addr);
- IPADDR2_COPY(&hdr->dipaddr, ipdst_addr);
- hdr->hwtype = PP_HTONS(HWTYPE_ETHERNET);
- hdr->proto = PP_HTONS(ETHTYPE_IP);
- /* set hwlen and protolen */
- hdr->hwlen = ETHARP_HWADDR_LEN;
- hdr->protolen = sizeof(ip_addr_t);
- ethhdr->type = PP_HTONS(ETHTYPE_ARP);
- /* send ARP query */
- result = netif->linkoutput(netif, p);
- ETHARP_STATS_INC(etharp.xmit);
- /* free ARP query packet */
- pbuf_free(p);
- p = NULL;
- /* could not allocate pbuf for ARP request */
- return result;
- }
- /**
- * Send an ARP request packet asking for ipaddr.
- *
- * @param netif the lwip network interface on which to send the request
- * @param ipaddr the IP address for which to ask
- * @return ERR_OK if the request has been sent
- * ERR_MEM if the ARP packet couldn't be allocated
- * any other err_t on failure
- */
- err_t
- etharp_request(struct netif *netif, ip_addr_t *ipaddr)
- {
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_request: sending ARP request.\n"));
- return etharp_raw(netif, (struct eth_addr *)netif->hwaddr, ðbroadcast,
- (struct eth_addr *)netif->hwaddr, &netif->ip_addr, ðzero,
- ipaddr, ARP_REQUEST);
- }
- #endif /* LWIP_ARP */
- /**
- * Process received ethernet frames. Using this function instead of directly
- * calling ip_input and passing ARP frames through etharp in ethernetif_input,
- * the ARP cache is protected from concurrent access.
- *
- * @param p the recevied packet, p->payload pointing to the ethernet header
- * @param netif the network interface on which the packet was received
- */
- err_t
- ethernet_input(struct pbuf *p, struct netif *netif)
- {
- struct eth_hdr* ethhdr;
- u16_t type;
- s16_t ip_hdr_offset = SIZEOF_ETH_HDR;
- if (p->len <= SIZEOF_ETH_HDR) {
- /* a packet with only an ethernet header (or less) is not valid for us modify by ives at 2014.4.24*/
- ETHARP_STATS_INC(etharp.proterr);
- ETHARP_STATS_INC(etharp.drop);
- goto free_and_return;
- }
- /* points to packet payload, which starts with an Ethernet header */
- ethhdr = (struct eth_hdr *)p->payload;
- LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE,
- ("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",
- (unsigned)ethhdr->dest.addr[0], (unsigned)ethhdr->dest.addr[1], (unsigned)ethhdr->dest.addr[2],
- (unsigned)ethhdr->dest.addr[3], (unsigned)ethhdr->dest.addr[4], (unsigned)ethhdr->dest.addr[5],
- (unsigned)ethhdr->src.addr[0], (unsigned)ethhdr->src.addr[1], (unsigned)ethhdr->src.addr[2],
- (unsigned)ethhdr->src.addr[3], (unsigned)ethhdr->src.addr[4], (unsigned)ethhdr->src.addr[5],
- (unsigned)htons(ethhdr->type)));
- type = ethhdr->type;
- #if ETHARP_SUPPORT_VLAN
- if (type == PP_HTONS(ETHTYPE_VLAN)) {
- struct eth_vlan_hdr *vlan = (struct eth_vlan_hdr*)(((char*)ethhdr) + SIZEOF_ETH_HDR);
- if (p->len <= SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR) {
- /* a packet with only an ethernet/vlan header (or less) is not valid for us modify by ives at 2014.4.24*/
- ETHARP_STATS_INC(etharp.proterr);
- ETHARP_STATS_INC(etharp.drop);
- goto free_and_return;
- }
- #ifdef ETHARP_VLAN_CHECK /* if not, allow all VLANs */
- if (VLAN_ID(vlan) != ETHARP_VLAN_CHECK) {
- /* silently ignore this packet: not for our VLAN */
- pbuf_free(p);
- return ERR_OK;
- }
- #endif /* ETHARP_VLAN_CHECK */
- type = vlan->tpid;
- ip_hdr_offset = SIZEOF_ETH_HDR + SIZEOF_VLAN_HDR;
- }
- #endif /* ETHARP_SUPPORT_VLAN */
- #if LWIP_ARP_FILTER_NETIF
- netif = LWIP_ARP_FILTER_NETIF_FN(p, netif, htons(type));
- #endif /* LWIP_ARP_FILTER_NETIF*/
- switch (type) {
- #if LWIP_ARP
- /* IP packet? */
- case PP_HTONS(ETHTYPE_IP):
- if (!(netif->flags & NETIF_FLAG_ETHARP)) {
- goto free_and_return;
- }
- #if ETHARP_TRUST_IP_MAC
- /* update ARP table */
- etharp_ip_input(netif, p);
- #endif /* ETHARP_TRUST_IP_MAC */
- /* skip Ethernet header */
- if(pbuf_header(p, -ip_hdr_offset)) {
- LWIP_ASSERT("Can't move over header in packet", 0);
- goto free_and_return;
- } else {
- /* pass to IP layer */
- ip_input(p, netif);
- }
- break;
- case PP_HTONS(ETHTYPE_ARP):
- if (!(netif->flags & NETIF_FLAG_ETHARP)) {
- goto free_and_return;
- }
- /* pass p to ARP module */
- etharp_arp_input(netif, (struct eth_addr*)(netif->hwaddr), p);
- break;
- #endif /* LWIP_ARP */
- #if PPPOE_SUPPORT
- case PP_HTONS(ETHTYPE_PPPOEDISC): /* PPP Over Ethernet Discovery Stage */
- pppoe_disc_input(netif, p);
- break;
- case PP_HTONS(ETHTYPE_PPPOE): /* PPP Over Ethernet Session Stage */
- pppoe_data_input(netif, p);
- break;
- #endif /* PPPOE_SUPPORT */
- default:
- ETHARP_STATS_INC(etharp.proterr);
- ETHARP_STATS_INC(etharp.drop);
- goto free_and_return;
- }
- /* This means the pbuf is freed or consumed,
- so the caller doesn't have to free it again */
- return ERR_OK;
- free_and_return:
- pbuf_free(p);
- return ERR_OK;
- }
- #endif /* LWIP_ARP || LWIP_ETHERNET */
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