void route_discovery_timeout(void *arg) {
seek_list_t *seek_entry;
seek_entry = (seek_list_t *)arg;
/* Sanity check... */
if(seek_entry == NULL)
return;
#ifdef DEBUG
log(LOG_DEBUG, 0, "route_discovery_timeout: %s",
ip_to_str(seek_entry->dest_addr));
#endif
if(seek_entry->reqs < RREQ_RETRIES) {
RREQ *rreq;
if(use_expanding_ring_search) {
if(seek_entry->ttl < TTL_THRESHOLD)
seek_entry->ttl += TTL_INCREMENT;
else {
seek_entry->ttl = NET_DIAMETER;
seek_entry->reqs++;
}
/* Set a new timer for seeking this destination */
seek_entry->timer_id = timer_new(2*seek_entry->ttl*NODE_TRAVERSAL_TIME,
route_discovery_timeout, seek_entry);
} else {
seek_entry->reqs++;
seek_entry->timer_id = timer_new(NET_TRAVERSAL_TIME,
route_discovery_timeout, seek_entry);
}
rreq = rreq_create(seek_entry->flags, seek_entry->dest_addr,
seek_entry->dest_seqno);
aodv_socket_send((AODV_msg *)rreq, AODV_BROADCAST, RREQ_SIZE,
seek_entry->ttl);
} else {
packet_buff_drop(seek_entry->dest_addr);
#ifdef DEBUG
log(LOG_DEBUG, 0, "route_discovery_timeout: NO ROUTE FOUND!");
#endif
seek_entry->timer_id = 0;
/* Send an ICMP Destination Host Unreachable to the application: */
if(seek_entry->ipd)
icmp_send_host_unreachable(this_host->ipaddr, seek_entry->ipd->data,
seek_entry->ipd->len);
seek_list_remove(seek_entry->dest_addr);
}
}
/* if packet->interface = NULL then the packet has been generated by the router */
void ip_forward(struct sr_packet * packet)
{
struct ip * ip_hdr = IP_HDR(packet);
uint32_t next_hop;
char thru_interface[SR_NAMELEN];
/* if the destination is to one of our ports, then just forward it there */
if(interface_list_get_interface_by_ip(INTERFACE_LIST(packet->sr), ip_hdr->ip_dst.s_addr))
{
ip_handle_incoming_packet(packet);
}
else
{
if(forwarding_table_lookup_next_hop(ROUTER(packet->sr)->fwd_table,
ip_hdr->ip_dst.s_addr, &next_hop, thru_interface,
interface_list_inbound(packet->sr, packet->interface)) &&
interface_list_forward_packet(packet->sr, packet->interface, thru_interface))
{
if(next_hop == 0)
{
next_hop = ip_hdr->ip_dst.s_addr;
}
ip_hdr->ip_ttl --;
ip_hdr->ip_sum = checksum_ipheader(ip_hdr);
ip_send(packet,next_hop,thru_interface);
}
else
{
if(forwarding_table_lookup_next_hop(ROUTER(packet->sr)->fwd_table,
ip_hdr->ip_src.s_addr, 0,0,
interface_list_inbound(packet->sr, packet->interface)))
{
icmp_send_host_unreachable(packet);
}
}
}
}
void NS_CLASS route_discovery_timeout(void *arg)
{
struct timeval now;
seek_list_t *seek_entry;
rt_table_t *rt, *repair_rt;
seek_entry = (seek_list_t *) arg;
#define TTL_VALUE seek_entry->ttl
/* Sanity check... */
if (!seek_entry)
return;
gettimeofday(&now, NULL);
DEBUG(LOG_DEBUG, 0, "%s", ip_to_str(seek_entry->dest_addr));
if (seek_entry->reqs < RREQ_RETRIES) {
if (expanding_ring_search) {
if (TTL_VALUE < TTL_THRESHOLD)
TTL_VALUE += TTL_INCREMENT;
else {
TTL_VALUE = NET_DIAMETER;
seek_entry->reqs++;
}
/* Set a new timer for seeking this destination */
timer_set_timeout(&seek_entry->seek_timer, RING_TRAVERSAL_TIME);
} else {
seek_entry->reqs++;
timer_set_timeout(&seek_entry->seek_timer,
seek_entry->reqs * 2 * NET_TRAVERSAL_TIME);
}
/* AODV should use a binary exponential backoff RREP waiting
time. */
DEBUG(LOG_DEBUG, 0, "Seeking %s ttl=%d wait=%d",
ip_to_str(seek_entry->dest_addr),
TTL_VALUE, 2 * TTL_VALUE * NODE_TRAVERSAL_TIME);
/* A routing table entry waiting for a RREP should not be expunged
before 2 * NET_TRAVERSAL_TIME... */
rt = rt_table_find(seek_entry->dest_addr);
if (rt && timeval_diff(&rt->rt_timer.timeout, &now) <
(2 * NET_TRAVERSAL_TIME))
rt_table_update_timeout(rt, 2 * NET_TRAVERSAL_TIME);
rreq_send(seek_entry->dest_addr, seek_entry->dest_seqno,
TTL_VALUE, seek_entry->flags);
} else {
packet_queue_drop(seek_entry->dest_addr);
DEBUG(LOG_DEBUG, 0, "NO ROUTE FOUND!");
#ifndef NS_PORT
/* Send an ICMP Destination Host Unreachable to the application: */
if (seek_entry->ipd)
icmp_send_host_unreachable(seek_entry->ipd->data,
seek_entry->ipd->len);
#endif
repair_rt = rt_table_find(seek_entry->dest_addr);
seek_list_remove(seek_entry);
/* If this route has been in repair, then we should timeout
the route at this point. */
if (repair_rt && (repair_rt->flags & RT_REPAIR)) {
DEBUG(LOG_DEBUG, 0, "REPAIR for %s failed!",
ip_to_str(repair_rt->dest_addr));
local_repair_timeout(repair_rt);
}
}
}
