1 /**
2 * @file
3 *
4 * Ethernet output for IPv6. Uses ND tables for link-layer addressing.
5 */
6
7 /*
8 * Copyright (c) 2010 Inico Technologies Ltd.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without modification,
12 * are permitted provided that the following conditions are met:
13 *
14 * 1. Redistributions of source code must retain the above copyright notice,
15 * this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright notice,
17 * this list of conditions and the following disclaimer in the documentation
18 * and/or other materials provided with the distribution.
19 * 3. The name of the author may not be used to endorse or promote products
20 * derived from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
23 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
24 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
25 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
26 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
27 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
30 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
31 * OF SUCH DAMAGE.
32 *
33 * This file is part of the lwIP TCP/IP stack.
34 *
35 * Author: Ivan Delamer <delamer@inicotech.com>
36 *
37 *
38 * Please coordinate changes and requests with Ivan Delamer
39 * <delamer@inicotech.com>
40 */
41
42 #include "lwip/opt.h"
43
44 #if LWIP_IPV6 && LWIP_ETHERNET
45
46 #include "lwip/ethip6.h"
47 #include "lwip/nd6.h"
48 #include "lwip/pbuf.h"
49 #include "lwip/ip6.h"
50 #include "lwip/ip6_addr.h"
51 #include "lwip/inet_chksum.h"
52 #include "lwip/netif.h"
53 #include "lwip/icmp6.h"
54 #include "lwip/prot/ethernet.h"
55 #include "netif/ethernet.h"
56
57 #include <string.h>
58
59 /**
60 * Resolve and fill-in Ethernet address header for outgoing IPv6 packet.
61 *
62 * For IPv6 multicast, corresponding Ethernet addresses
63 * are selected and the packet is transmitted on the link.
64 *
65 * For unicast addresses, ...
66 *
67 * @todo anycast addresses
68 *
69 * @param netif The lwIP network interface which the IP packet will be sent on.
70 * @param q The pbuf(s) containing the IP packet to be sent.
71 * @param ip6addr The IP address of the packet destination.
72 *
73 * @return
74 * - ERR_RTE No route to destination (no gateway to external networks),
75 * or the return type of either nd6_queue_packet() or ethernet_output().
76 */
77 err_t
ethip6_output(struct netif * netif,struct pbuf * q,const ip6_addr_t * ip6addr)78 ethip6_output(struct netif *netif, struct pbuf *q, const ip6_addr_t *ip6addr)
79 {
80 struct eth_addr dest;
81 s8_t i;
82
83 /* multicast destination IP address? */
84 if (ip6_addr_ismulticast(ip6addr)) {
85 /* Hash IP multicast address to MAC address.*/
86 dest.addr[0] = 0x33;
87 dest.addr[1] = 0x33;
88 dest.addr[2] = ((const u8_t *)(&(ip6addr->addr[3])))[0];
89 dest.addr[3] = ((const u8_t *)(&(ip6addr->addr[3])))[1];
90 dest.addr[4] = ((const u8_t *)(&(ip6addr->addr[3])))[2];
91 dest.addr[5] = ((const u8_t *)(&(ip6addr->addr[3])))[3];
92
93 /* Send out. */
94 return ethernet_output(netif, q, (struct eth_addr*)(netif->hwaddr), &dest, ETHTYPE_IPV6);
95 }
96
97 /* We have a unicast destination IP address */
98 /* @todo anycast? */
99 /* Get next hop record. */
100 i = nd6_get_next_hop_entry(ip6addr, netif);
101 if (i < 0) {
102 /* failed to get a next hop neighbor record. */
103 return ERR_MEM;
104 }
105
106 /* Now that we have a destination record, send or queue the packet. */
107 if (neighbor_cache[i].state == ND6_STALE) {
108 /* Switch to delay state. */
109 neighbor_cache[i].state = ND6_DELAY;
110 neighbor_cache[i].counter.delay_time = LWIP_ND6_DELAY_FIRST_PROBE_TIME / ND6_TMR_INTERVAL;
111 }
112 /* @todo should we send or queue if PROBE? send for now, to let unicast NS pass. */
113 if ((neighbor_cache[i].state == ND6_REACHABLE) ||
114 (neighbor_cache[i].state == ND6_DELAY) ||
115 (neighbor_cache[i].state == ND6_PROBE)) {
116
117 /* Send out. */
118 SMEMCPY(dest.addr, neighbor_cache[i].lladdr, 6);
119 return ethernet_output(netif, q, (struct eth_addr*)(netif->hwaddr), &dest, ETHTYPE_IPV6);
120 }
121
122 /* We should queue packet on this interface. */
123 return nd6_queue_packet(i, q);
124 }
125
126 #endif /* LWIP_IPV6 && LWIP_ETHERNET */
127