+ /* Packets received by this function were previously sent by us, so
+ * any comparisons should be to the output values, not the input.
+ * However, it's not really worth it to have a hash table based on
+ * output keys (especially since ICMP error handling of tunneled packets
+ * isn't that reliable anyways). Therefore, we do a lookup based on the
+ * out key as if it were the in key and then check to see if the input
+ * and output keys are the same. */
+ if (mutable->port_config.in_key != mutable->port_config.out_key)