/**
* Resolve and fill-in Ethernet address header for outgoing IPv6 packet.
*
* For IPv6 multicast, corresponding Ethernet addresses
* are selected and the packet is transmitted on the link.
*
* For unicast addresses, ...
*
* @TODO anycast addresses
*
* @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 ip6addr 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
ethip6_output(struct netif *netif, struct pbuf *q, ip6_addr_t *ip6addr)
{
struct eth_addr dest;
s8_t i;
/* 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"));
return ERR_BUF;
}
/* multicast destination IP address? */
if (ip6_addr_ismulticast(ip6addr)) {
/* Hash IP multicast address to MAC address.*/
dest.addr[0] = 0x33;
dest.addr[1] = 0x33;
dest.addr[2] = ((u8_t *)(&(ip6addr->addr[3])))[0];
dest.addr[3] = ((u8_t *)(&(ip6addr->addr[3])))[1];
dest.addr[4] = ((u8_t *)(&(ip6addr->addr[3])))[2];
dest.addr[5] = ((u8_t *)(&(ip6addr->addr[3])))[3];
/* Send out. */
return ethip6_send(netif, q, (struct eth_addr*)(netif->hwaddr), &dest);
}
/* We have a unicast destination IP address */
/* TODO anycast? */
/* Get next hop record. */
i = nd6_get_next_hop_entry(ip6addr, netif);
if (i < 0) {
/* failed to get a next hop neighbor record. */
return ERR_MEM;
}
/* Now that we have a destination record, send or queue the packet. */
if (neighbor_cache[i].state == ND6_STALE) {
/* Switch to delay state. */
neighbor_cache[i].state = ND6_DELAY;
neighbor_cache[i].counter.delay_time = LWIP_ND6_DELAY_FIRST_PROBE_TIME;
}
/* TODO should we send or queue if PROBE? send for now, to let unicast NS pass. */
if ((neighbor_cache[i].state == ND6_REACHABLE) ||
(neighbor_cache[i].state == ND6_DELAY) ||
(neighbor_cache[i].state == ND6_PROBE)) {
/* Send out. */
SMEMCPY(dest.addr, neighbor_cache[i].lladdr, 6);
return ethip6_send(netif, q, (struct eth_addr*)(netif->hwaddr), &dest);
}
/* We should queue packet on this interface. */
pbuf_header(q, -(s16_t)SIZEOF_ETH_HDR);
return nd6_queue_packet(i, q);
}
/**
* Resolve and fill-in Ethernet address header for outgoing IPv6 packet.
*
* For IPv6 multicast, corresponding Ethernet addresses
* are selected and the packet is transmitted on the link.
*
* For unicast addresses, ...
*
* @todo anycast addresses
*
* @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 ip6addr 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 nd6_queue_packet() or ethernet_output().
*/
err_t
ethip6_output(struct netif *netif, struct pbuf *q, const ip6_addr_t *ip6addr)
{
struct eth_addr dest;
s8_t i;
/* multicast destination IP address? */
if (ip6_addr_ismulticast(ip6addr)) {
/* Hash IP multicast address to MAC address.*/
dest.addr[0] = 0x33;
dest.addr[1] = 0x33;
dest.addr[2] = ((const u8_t *)(&(ip6addr->addr[3])))[0];
dest.addr[3] = ((const u8_t *)(&(ip6addr->addr[3])))[1];
dest.addr[4] = ((const u8_t *)(&(ip6addr->addr[3])))[2];
dest.addr[5] = ((const u8_t *)(&(ip6addr->addr[3])))[3];
/* Send out. */
return ethernet_output(netif, q, (struct eth_addr*)(netif->hwaddr), &dest, ETHTYPE_IPV6);
}
/* We have a unicast destination IP address */
/* @todo anycast? */
/* Get next hop record. */
i = nd6_get_next_hop_entry(ip6addr, netif);
if (i < 0) {
/* failed to get a next hop neighbor record. */
return ERR_MEM;
}
/* Now that we have a destination record, send or queue the packet. */
if (neighbor_cache[i].state == ND6_STALE) {
/* Switch to delay state. */
neighbor_cache[i].state = ND6_DELAY;
neighbor_cache[i].counter.delay_time = LWIP_ND6_DELAY_FIRST_PROBE_TIME / ND6_TMR_INTERVAL;
}
/* @todo should we send or queue if PROBE? send for now, to let unicast NS pass. */
if ((neighbor_cache[i].state == ND6_REACHABLE) ||
(neighbor_cache[i].state == ND6_DELAY) ||
(neighbor_cache[i].state == ND6_PROBE)) {
/* Send out. */
SMEMCPY(dest.addr, neighbor_cache[i].lladdr, 6);
return ethernet_output(netif, q, (struct eth_addr*)(netif->hwaddr), &dest, ETHTYPE_IPV6);
}
/* We should queue packet on this interface. */
return nd6_queue_packet(i, q);
}
