/**
* 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
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;
#if ARP_QUEUEING
/* this is where we will send out queued packets! */
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);
/* send the queued IP packet */
etharp_send_ip(netif, p, (struct eth_addr*)(netif->hwaddr), ethaddr);
/* free the queued IP packet */
pbuf_free(p);
}
#endif /* ARP_QUEUEING */
return ERR_OK;
}
/**
* 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
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;
}