Implementing a PoC for VLS signer

[vincenzopalazzo]

Background

Given the absence of a widely adopted full node for rust-lightning (which we aim to become one of), there exists a notable project called Validating Lightning Signer (VLS) at vls.tech that supports rust-lightning but lacks a compatible project to collaborate with.

From our perspective, we are a small project with significant ambitions. Incorporating the VLS signer as the default signer within Lampo can aid us in enhancing various aspects of our design and ensuring fund security by entrusting responsibility to individuals dedicated to fund safety.

Goal

This SoB project seeks to experiment with Lampo and VLS by implementing the different signers supported by VLS (including the local and remote versions) within Lampo.

The main steps for this SoB project are:

• Explore using VLS within a rust-lightning node with the lnrod node.
• Implement and potentially extend the common interface of a signer exposed by Lampo to facilitate signer swapping at compile time (e.g., utilizing a Signer trait or leveraging the ldk).
• Initially implement the local signer and evaluate its ability to pass Lampo's integration tests.

Notes

There was a previous attempt at this #284 please see the reason on why it is still not merged

I started to write down the code but I did not have the time to finish #289

---

This is a project for the https://planb.network