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Simplified update_arp_entry().

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likewise 2004-05-06 00:14:39 +00:00
parent 273612b251
commit 7b803465ad
1 changed files with 59 additions and 65 deletions
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124
src/netif/etharp.c
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@ -102,7 +102,7 @@ static struct etharp_entry arp_table[ARP_TABLE_SIZE];
static s8_t find_arp_entry(void);
/** ask update_arp_entry() to add instead of merely update an ARP entry */
#define ARP_INSERT_FLAG 1
static struct pbuf *update_arp_entry(struct netif *netif, struct ip_addr *ipaddr, struct eth_addr *ethaddr, u8_t flags);
static err_t update_arp_entry(struct netif *netif, struct ip_addr *ipaddr, struct eth_addr *ethaddr, u8_t flags);
/**
* Initializes ARP module.
*/
@ -257,92 +257,86 @@ update_arp_entry(struct netif *netif, struct ip_addr *ipaddr, struct eth_addr *e
LWIP_DEBUGF(ETHARP_DEBUG | DBG_TRACE, ("update_arp_entry: will not add non-unicast IP address to ARP cache\n"));
return ERR_ARG;
}
/* Walk through the ARP mapping table and try to find an entry to update.
* If none is found, a new IP -> MAC address mapping is inserted. */
/* find existing ARP entry */
for (i = 0; i < ARP_TABLE_SIZE; ++i) {
/* Check if the source IP address of the incoming packet matches
* the IP address in this ARP table entry. */
if (arp_table[i].state != ETHARP_STATE_EMPTY &&
ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
/* pending entry? */
if (arp_table[i].state == ETHARP_STATE_PENDING) {
/* pending entry? */
if (arp_table[i].state == ETHARP_STATE_PENDING) {
/* source IP address of packet matches IP address in ARP entry? */
if (ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
LWIP_DEBUGF(ETHARP_DEBUG | DBG_TRACE, ("update_arp_entry: pending entry %u goes stable\n", i));
/* A pending entry was found, mark it stable */
arp_table[i].state = ETHARP_STATE_STABLE;
/* fall-through to next if */
/* IP addresses should only occur at most once in the ARP entry */
break;
}
/* stable entry? (possibly just marked stable) */
if (arp_table[i].state == ETHARP_STATE_STABLE) {
}
/* stable entry? */
else if (arp_table[i].state == ETHARP_STATE_STABLE) {
/* source IP address of packet matches IP address in ARP entry? */
if (ip_addr_cmp(ipaddr, &arp_table[i].ipaddr)) {
LWIP_DEBUGF(ETHARP_DEBUG | DBG_TRACE, ("update_arp_entry: updating stable entry %u\n", i));
/* An old entry found, update this and return. */
for (k = 0; k < netif->hwaddr_len; ++k) {
arp_table[i].ethaddr.addr[k] = ethaddr->addr[k];
}
/* reset time stamp */
arp_table[i].ctime = 0;
/* this is where we will send out queued packets! */
#if ARP_QUEUEING
while (arp_table[i].p != NULL) {
/* get the first packet on the queue (if any) */
struct pbuf *p = arp_table[i].p;
/* Ethernet header */
struct eth_hdr *ethhdr = p->payload;;
/* remember (and reference) remainder of queue */
/* note: this will also terminate the p pbuf chain */
arp_table[i].p = pbuf_dequeue(p);
/* fill-in Ethernet header */
for (k = 0; k < netif->hwaddr_len; ++k) {
ethhdr->dest.addr[k] = ethaddr->addr[k];
ethhdr->src.addr[k] = netif->hwaddr[k];
}
ethhdr->type = htons(ETHTYPE_IP);
LWIP_DEBUGF(ETHARP_DEBUG | DBG_TRACE, ("update_arp_entry: sending queued IP packet %p.\n", (void *)p));
/* send the queued IP packet */
netif->linkoutput(netif, p);
/* free the queued IP packet */
pbuf_free(p);
}
#endif
/* IP addresses should only occur once in the ARP entry, we are done */
return ERR_OK;
/* IP addresses should only occur at most once in the ARP entry */
break;
}
} /* if STABLE */
} /* for all ARP entries */
}
}
/* no matching ARP entry was found */
LWIP_ASSERT("update_arp_entry: i == ARP_TABLE_SIZE", i == ARP_TABLE_SIZE);
LWIP_DEBUGF(ETHARP_DEBUG | DBG_TRACE, ("update_arp_entry: IP address not yet in table\n"));
/* allowed to insert a new entry? */
if (flags & ARP_INSERT_FLAG)
/* no matching ARP entry was found and allowed to insert a new entry? */
if (i == ARP_TABLE_SIZE) && (flags & ARP_INSERT_FLAG))
{
LWIP_DEBUGF(ETHARP_DEBUG | DBG_TRACE, ("update_arp_entry: adding entry to table\n"));
/* find an empty or old entry. */
i = find_arp_entry();
if (i < 0) {
LWIP_DEBUGF(ETHARP_DEBUG | DBG_TRACE, ("update_arp_entry: no available entry found\n"));
LWIP_DEBUGF(ETHARP_DEBUG | DBG_TRACE, ("update_arp_entry: could not add new entry\n"));
return (err_t)i;
}
/* set IP address */
ip_addr_set(&arp_table[i].ipaddr, ipaddr);
/* set Ethernet hardware address */
for (k = 0; k < netif->hwaddr_len; ++k) {
arp_table[i].ethaddr.addr[k] = ethaddr->addr[k];
}
/* reset time-stamp */
arp_table[i].ctime = 0;
LWIP_DEBUGF(ETHARP_DEBUG | DBG_TRACE, ("update_arp_entry: adding new entry to table\n"));
/* mark as stable */
arp_table[i].state = ETHARP_STATE_STABLE;
/* no queued packet */
/* set IP address */
ip_addr_set(&arp_table[i].ipaddr, ipaddr);
#if ARP_QUEUEING
arp_table[i].p = NULL;
#endif
/* fall-through to update Ethernet address */
}
else
{
/* found a matching stable entry? */
if (i != ARP_TABLE_SIZE) && (arp_table[i].state == ETHARP_STATE_STABLE)) {
LWIP_DEBUGF(ETHARP_DEBUG | DBG_TRACE, ("update_arp_entry: updating stable entry %u\n", i));
/* update address */
for (k = 0; k < netif->hwaddr_len; ++k) {
arp_table[i].ethaddr.addr[k] = ethaddr->addr[k];
}
/* reset time stamp */
arp_table[i].ctime = 0;
/* this is where we will send out queued packets! */
#if ARP_QUEUEING
while (arp_table[i].p != NULL) {
/* get the first packet on the queue (if any) */
struct pbuf *p = arp_table[i].p;
/* Ethernet header */
struct eth_hdr *ethhdr = p->payload;;
/* remember (and reference) remainder of queue */
/* note: this will also terminate the p pbuf chain */
arp_table[i].p = pbuf_dequeue(p);
/* fill-in Ethernet header */
for (k = 0; k < netif->hwaddr_len; ++k) {
ethhdr->dest.addr[k] = ethaddr->addr[k];
ethhdr->src.addr[k] = netif->hwaddr[k];
}
ethhdr->type = htons(ETHTYPE_IP);
LWIP_DEBUGF(ETHARP_DEBUG | DBG_TRACE, ("update_arp_entry: sending queued IP packet %p.\n", (void *)p));
/* send the queued IP packet */
netif->linkoutput(netif, p);
/* free the queued IP packet */
pbuf_free(p);
}
#endif
} else {
LWIP_DEBUGF(ETHARP_DEBUG | DBG_TRACE, ("update_arp_entry: no matching stable entry to update\n"));
}
return NULL;
return ERR_OK;
}
/**