/*
* XXX: ip6_route is too eager to return single/default netif, and
* forwarding logic is different from the logic to select outgoing
* interface for our own packets anyway.
*/
static struct netif *
ip6_route_fwd(struct ip6_addr *dest)
{
struct netif *netif;
s8_t i;
/* Link-local addresses are not routable. */
if (ip6_addr_islinklocal(dest)) {
return NULL;
}
/* See if the destination subnet matches a configured address. */
for(netif = netif_list; netif != NULL; netif = netif->next) {
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
ip6_addr_netcmp(dest, netif_ip6_addr(netif, i))) {
return netif;
}
}
}
/* Get the netif for a suitable router. */
i = nd6_select_router(dest, NULL);
if (i >= 0) {
if (default_router_list[i].neighbor_entry != NULL) {
if (default_router_list[i].neighbor_entry->netif != NULL) {
return default_router_list[i].neighbor_entry->netif;
}
}
}
/* no matching netif found */
return NULL;
}
/**
* Finds the appropriate network interface for a given IPv6 address. It tries to select
* a netif following a sequence of heuristics:
* 1) if there is only 1 netif, return it
* 2) if the destination is a link-local address, try to match the src address to a netif.
* this is a tricky case because with multiple netifs, link-local addresses only have
* meaning within a particular subnet/link.
* 3) tries to match the destination subnet to a configured address
* 4) tries to find a router
* 5) tries to match the source address to the netif
* 6) returns the default netif, if configured
*
* @param src the source IPv6 address, if known
* @param dest the destination IPv6 address for which to find the route
* @return the netif on which to send to reach dest
*/
struct netif *
ip6_route(const ip6_addr_t *src, const ip6_addr_t *dest)
{
struct netif *netif;
s8_t i;
#ifdef LWIP_HOOK_IP6_ROUTE
netif = LWIP_HOOK_IP6_ROUTE(src, dest);
if (netif != NULL) {
return netif;
}
#endif
/* If single netif configuration, fast return. */
if ((netif_list != NULL) && (netif_list->next == NULL)) {
if (!netif_is_up(netif_list) || !netif_is_link_up(netif_list)) {
return NULL;
}
return netif_list;
}
/* Special processing for link-local addresses. */
if (ip6_addr_islinklocal(dest)) {
if (ip6_addr_isany(src)) {
/* Use default netif, if Up. */
if (!netif_is_up(netif_default) || !netif_is_link_up(netif_default)) {
return NULL;
}
return netif_default;
}
/* Try to find the netif for the source address, checking that link is up. */
for (netif = netif_list; netif != NULL; netif = netif->next) {
if (!netif_is_up(netif) || !netif_is_link_up(netif)) {
continue;
}
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
ip6_addr_cmp(src, netif_ip6_addr(netif, i))) {
return netif;
}
}
}
/* netif not found, use default netif, if up */
if (!netif_is_up(netif_default) || !netif_is_link_up(netif_default)) {
return NULL;
}
return netif_default;
}
/* See if the destination subnet matches a configured address. */
for (netif = netif_list; netif != NULL; netif = netif->next) {
if (!netif_is_up(netif) || !netif_is_link_up(netif)) {
continue;
}
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
ip6_addr_netcmp(dest, netif_ip6_addr(netif, i))) {
return netif;
}
}
}
/* Get the netif for a suitable router. */
i = nd6_select_router(dest, NULL);
if (i >= 0) {
if (default_router_list[i].neighbor_entry != NULL) {
if (default_router_list[i].neighbor_entry->netif != NULL) {
if (netif_is_up(default_router_list[i].neighbor_entry->netif) && netif_is_link_up(default_router_list[i].neighbor_entry->netif)) {
return default_router_list[i].neighbor_entry->netif;
}
}
}
}
/* try with the netif that matches the source address. */
if (!ip6_addr_isany(src)) {
for (netif = netif_list; netif != NULL; netif = netif->next) {
if (!netif_is_up(netif) || !netif_is_link_up(netif)) {
continue;
}
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
ip6_addr_cmp(src, netif_ip6_addr(netif, i))) {
return netif;
}
}
}
}
#if LWIP_NETIF_LOOPBACK && !LWIP_HAVE_LOOPIF
/* loopif is disabled, loopback traffic is passed through any netif */
if (ip6_addr_isloopback(dest)) {
/* don't check for link on loopback traffic */
if (netif_is_up(netif_default)) {
return netif_default;
}
/* default netif is not up, just use any netif for loopback traffic */
for (netif = netif_list; netif != NULL; netif = netif->next) {
if (netif_is_up(netif)) {
return netif;
}
}
return NULL;
}
#endif /* LWIP_NETIF_LOOPBACK && !LWIP_HAVE_LOOPIF */
/* no matching netif found, use default netif, if up */
if (!netif_is_up(netif_default) || !netif_is_link_up(netif_default)) {
return NULL;
}
return netif_default;
}
/**
* Finds the appropriate network interface for a given IPv6 address. It tries to select
* a netif following a sequence of heuristics:
* 1) if there is only 1 netif, return it
* 2) if the destination is a link-local address, try to match the src address to a netif.
* this is a tricky case because with multiple netifs, link-local addresses only have
* meaning within a particular subnet/link.
* 3) tries to match the destination subnet to a configured address
* 4) tries to find a router
* 5) tries to match the source address to the netif
* 6) returns the default netif, if configured
*
* @param src the source IPv6 address, if known
* @param dest the destination IPv6 address for which to find the route
* @return the netif on which to send to reach dest
*/
struct netif *
ip6_route(struct ip6_addr *src, struct ip6_addr *dest)
{
struct netif *netif;
s8_t i;
/* If single netif configuration, fast return. */
if ((netif_list != NULL) && (netif_list->next == NULL)) {
return netif_list;
}
/* Special processing for link-local addresses. */
if (ip6_addr_islinklocal(dest)) {
if (ip6_addr_isany(src)) {
/* Use default netif. */
return netif_default;
}
/* Try to find the netif for the source address. */
for(netif = netif_list; netif != NULL; netif = netif->next) {
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
ip6_addr_cmp(src, netif_ip6_addr(netif, i))) {
return netif;
}
}
}
/* netif not found, use default netif */
return netif_default;
}
/* See if the destination subnet matches a configured address. */
for(netif = netif_list; netif != NULL; netif = netif->next) {
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
ip6_addr_netcmp(dest, netif_ip6_addr(netif, i))) {
return netif;
}
}
}
/* Get the netif for a suitable router. */
i = nd6_select_router(dest, NULL);
if (i >= 0) {
if (default_router_list[i].neighbor_entry != NULL) {
if (default_router_list[i].neighbor_entry->netif != NULL) {
return default_router_list[i].neighbor_entry->netif;
}
}
}
/* try with the netif that matches the source address. */
if (!ip6_addr_isany(src)) {
for(netif = netif_list; netif != NULL; netif = netif->next) {
for (i = 0; i < LWIP_IPV6_NUM_ADDRESSES; i++) {
if (ip6_addr_isvalid(netif_ip6_addr_state(netif, i)) &&
ip6_addr_cmp(src, netif_ip6_addr(netif, i))) {
return netif;
}
}
}
}
/* no matching netif found, use default netif */
return netif_default;
}