I think it should be possible to optionally whitelist outgoing connections - specifically those that are explicitly created through connect, addnode. Context: I regularly need to bypass this code in testing setups to be able to sync non-internet connected nodes: https://github.com/bitcoin/bitcoin/blob/master/src/net_processing.cpp#L1720
Also in the interest of symmetry I don’t see why whitelisting would only apply to incoming connections.
As it happens, I have a branch that allows nodes to be whitelisted through an RPC: https://github.com/jnewbery/bitcoin/tree/updatenode .
Context: the RPC is called updatenode so that it can be extended in future, eg to update the banscore for a node, or disconnect a node based on node id (at the moment, nodes can only be disconnected based on ip address).
I haven’t written any testcases for this yet, but feel free to take it if it’s helpful for your testing.
That seems useful in general.
I’m a little afraid that won’t work for my use-case because of the race between toggling ‘whitelist’ to 1 and making the connection. The other side will immediately send a getheaders, which could get ignored if it’s not in time (and IIRC it won’t send any, ever again, after that).
-whitelist netmask apply to outgoing connections as well. It seems straightforward but that may be an unexpected change of behavior.
