/** * 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); }
/** * 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 @ref etharp_state * * @return * - ERR_OK Successfully 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 etharp_update_arp_entry(struct netif *netif, const ip4_addr_t *ipaddr, struct eth_addr *ethaddr, u8_t flags) { s8_t i; LWIP_ASSERT("netif->hwaddr_len == ETH_HWADDR_LEN", netif->hwaddr_len == ETH_HWADDR_LEN); LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_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), (u16_t)ethaddr->addr[0], (u16_t)ethaddr->addr[1], (u16_t)ethaddr->addr[2], (u16_t)ethaddr->addr[3], (u16_t)ethaddr->addr[4], (u16_t)ethaddr->addr[5])); /* non-unicast address? */ if (ip4_addr_isany(ipaddr) || ip4_addr_isbroadcast(ipaddr, netif) || ip4_addr_ismulticast(ipaddr)) { LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_update_arp_entry: will not add non-unicast IP address to ARP cache\n")); return ERR_ARG; } /* find or create ARP entry */ i = etharp_find_entry(ipaddr, flags, netif); /* 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].state = ETHARP_STATE_STATIC; } else if (arp_table[i].state == ETHARP_STATE_STATIC) { /* found entry is a static type, don't overwrite it */ return ERR_VAL; } else #endif /* ETHARP_SUPPORT_STATIC_ENTRIES */ { /* mark it stable */ arp_table[i].state = ETHARP_STATE_STABLE; } /* record network interface */ arp_table[i].netif = netif; /* insert in SNMP ARP index tree */ mib2_add_arp_entry(netif, &arp_table[i].ipaddr); LWIP_DEBUGF(ETHARP_DEBUG | LWIP_DBG_TRACE, ("etharp_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 */ ethernet_output(netif, p, (struct eth_addr*)(netif->hwaddr), ethaddr, ETHTYPE_IP); /* 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(const ip4_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), (u16_t)ethaddr->addr[0], (u16_t)ethaddr->addr[1], (u16_t)ethaddr->addr[2], (u16_t)ethaddr->addr[3], (u16_t)ethaddr->addr[4], (u16_t)ethaddr->addr[5])); netif = ip4_route(ipaddr); if (netif == NULL) { return ERR_RTE; } return etharp_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(const ip4_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 = etharp_find_entry(ipaddr, ETHARP_FLAG_FIND_ONLY, NULL); /* bail out if no entry could be found */ if (i < 0) { return (err_t)i; } if (arp_table[i].state != ETHARP_STATE_STATIC) { /* entry wasn't a static entry, cannot remove it */ return ERR_ARG; } /* entry found, free it */ etharp_free_entry(i); return ERR_OK; }