CONFIG_IP_NF_TARGET_SAME is similar to SNAT/DNAT depending on chain: it takes a
range of addresses (`--to 1.2.3.4-1.2.3.7') and gives a client the same
source-/destination-address for each connection.

It has a --nodst option to make it not use the destination-ip in the
calculations when selecting the new source-ip

It has support for multiple ranges, including 1-address ranges.
