bool rreqtable_is_redundant(struct aodvv2_packet_data *packet_data)
{
struct aodvv2_rreq_entry *comparable_rreq;
timex_t now;
bool result;
mutex_lock(&rreqt_mutex);
comparable_rreq = _get_comparable_rreq(packet_data);
/* if there is no comparable rreq stored, add one and return false */
if (comparable_rreq == NULL) {
_add_rreq(packet_data);
result = false;
}
else {
int seqnum_comparison = seqnum_cmp(packet_data->origNode.seqnum, comparable_rreq->seqnum);
/*
* If two RREQs have the same
* metric type and OrigNode and Targnode addresses, the information from
* the one with the older Sequence Number is not needed in the table
*/
if (seqnum_comparison == -1) {
result = true;
}
if (seqnum_comparison == 1) {
/* Update RREQ table entry with new seqnum value */
comparable_rreq->seqnum = packet_data->origNode.seqnum;
}
/*
* in case they have the same Sequence Number, the one with the greater
* Metric value is not needed
*/
if (seqnum_comparison == 0) {
if (comparable_rreq->metric <= packet_data->origNode.metric) {
result = true;
}
/* Update RREQ table entry with new metric value */
comparable_rreq->metric = packet_data->origNode.metric;
}
/* Since we've changed RREQ info, update the timestamp */
vtimer_now(&now);
comparable_rreq->timestamp = now;
result = true;
}
mutex_unlock(&rreqt_mutex);
return result;
}
static enum rfc5444_result _cb_rerr_blocktlv_addresstlvs_okay(struct rfc5444_reader_tlvblock_context *cont)
{
#if ENABLE_DEBUG
/* cppcheck-suppress unusedVariable as nbuf is needed by VDEBUG. */
struct netaddr_str nbuf;
#endif
struct aodvv2_routing_entry_t *unreachable_entry;
struct rfc5444_reader_tlvblock_entry *tlv;
VDEBUG("%s()\n", __func__);
VDEBUG("\tmessage type: %d\n", cont->type);
VDEBUG("\taddr: %s\n", netaddr_to_string(&nbuf, &cont->addr));
/* Out of buffer size for more unreachable nodes. We're screwed, basically. */
if (num_unreachable_nodes == AODVV2_MAX_UNREACHABLE_NODES) {
return RFC5444_OKAY;
}
/* gather packet data */
packet_data.origNode.addr = cont->addr;
/* handle this unreachable node's SeqNum TLV */
/* cppcheck: suppress false positive on non-trivially initialized arrays.
* this is a known bug: http://trac.cppcheck.net/ticket/5497 */
/* cppcheck-suppress arrayIndexOutOfBounds */
tlv = _rerr_address_consumer_entries[RFC5444_MSGTLV_UNREACHABLE_NODE_SEQNUM].tlv;
if (tlv) {
VDEBUG("\ttlv RFC5444_MSGTLV_UNREACHABLE_NODE_SEQNUM: %d\n", *tlv->single_value);
packet_data.origNode.seqnum = *tlv->single_value;
}
/* Check if there is an entry for unreachable node in our routing table */
unreachable_entry = routingtable_get_entry(&packet_data.origNode.addr, packet_data.metricType);
if (unreachable_entry) {
VDEBUG("\t found possibly unreachable entry.\n");
/* check if route to unreachable node has to be marked as broken and RERR has to be forwarded */
if (netaddr_cmp(&unreachable_entry->nextHopAddr, &packet_data.sender) == 0
&& (!tlv || seqnum_cmp(unreachable_entry->seqnum, packet_data.origNode.seqnum) == 0)) {
unreachable_entry->state = ROUTE_STATE_INVALID;
unreachable_nodes[num_unreachable_nodes].addr = packet_data.origNode.addr;
unreachable_nodes[num_unreachable_nodes].seqnum = packet_data.origNode.seqnum;
num_unreachable_nodes++;
}
/* remove entry from FIB */
fib_remove_entry(packet_data.origNode.addr._addr, sizeof(ipv6_addr_t));
}
return RFC5444_OKAY;
}
bool routingtable_offers_improvement(struct aodvv2_routing_entry_t *rt_entry,
struct node_data *node_data)
{
/* (TODO only guaranteed for AODVV2_DEFAULT_METRIC_TYPE!)*/
bool is_loop_free = node_data->metric <= rt_entry->metric;
int stale = seqnum_cmp(node_data->seqnum, rt_entry->seqnum);
if ((stale == 1) /* New info is more recent and MUST be used */
|| ((stale == 0) && (node_data->metric < rt_entry->metric)) /* New info offers a better route and SHOULD be used */
|| ((stale == 0) && (node_data->metric >= rt_entry->metric) /* Route is not an improvement, */
&& (rt_entry->state == ROUTE_STATE_INVALID) /* but repairs an invalid route */
&& is_loop_free) /* and contains no loops */
) {
return true;
}
return false;
}
