[Lightning-dev] Proposal: Add support for proxying p2p connections to/from LND

[Alex Akselrod]

At NYDIG, we're considering ways to harden large LND deployments. Joost and I discussed that currently, when external untrusted peers make inbound connections, LND must verify the identity of the peer during the noise handshake, and it must do this before enforcing any potential key-based allow lists. This is done in the same process as the node's other critical tasks, such as monitoring the chain.

To reduce the attack area of the main node process, we'd like to propose a means to optionally separate the peer communication into a separate process: something like CLN's connectd, running separately, and the connections would be multiplexed over a single network connection initiated from the node to the proxy. The core of our current idea is demonstrated in a draft PR: https://github.com/lightningnetwork/lnd/pull/6843

I'd love some early feedback on the general direction of this. If this would be interesting, I'll build it out into a fully working feature.

Thanks,

Alex Akselrod