Here is my best guess about the config you are showing:
There's a part of the config you are not showing that specifies the destination IP address (say X) and port number (say Y) of an incoming packet.
The part that you show specifies how to rewrite the source IP address, source port number, destination IP address, and destination port number of the packet.
I.e., the rule overall says: if a packet arrives with destination IP address X and port number Y, then rewrite its source IP address, source port number, destination IP address, and destination port number in this way.
Am I guessing right?
There's a part of the config you are not showing that specifies the destination IP address (say X) and port number (say Y) of an incoming packet.
The part that you show specifies how to rewrite the source IP address, source port number, destination IP address, and destination port number of the packet.
I.e., the rule overall says: if a packet arrives with destination IP address X and port number Y, then rewrite its source IP address, source port number, destination IP address, and destination port number in this way.
Am I guessing right?
