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I'm writing a client for a badly-behaved UDP server: The server replies are sourced from an unpredictable IP address.
Using net.Dial(), I'm able to send a query to the server and provoke the expected response, but because the reply comes from a different IP address, attempts to read it from the net.Conn object never complete.
On the wire, the transaction looks like:
client-ip:client-ephemeral-port -> server-ip:server-well-known-port
surprise-ip:server-well-known-port -> client-ip:client-ephemeral-port
Everything's fine when the server replies from server-ip, rather than from surprise-ip.
Changing the server behavior isn't possible.
I think this means I'm going to need to abandon net.Dial() and get closer to the underlying socket behavior (hopefully in an OS-independent way).
I'm looking for examples of how to accommodate the server behavior, but the various UDP walkthroughs I've found so far seem the rely on 5-tuple "connection" behaviors.
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