spscand: a watch-only BIP352 silent payment scanner, with a web scanner

[NotATether]

I've released spscand 0.1.0, the standalone scanner for silent payments.

• Code (MIT): https://github.com/ZenulAbidin/spscand
• Web scanner: https://spscan.bitmixlist.org
• Latest version: v0.1.0 (GPG-signed)

What it does

It finds payments to your sp1 address (BIP352 1.1.2), tracks their spends and reorgs, and reports them through a local JSON API and a webhook.

Where it gets blocks

It never asks a server about an address, output or transaction. You can get blocks from your own node, a blindbit server, or BIP352 filters. Tor works with proxy = "socks5h://127.0.0.1:9050" including onion connections and peers

Web scanner

If you don't want to install anything, spscan.bitmixlist.org scans a wallet from a browser. There is also a server mode for long histories, but it can see your scan key. Results are deleted within 24 hours.

libspscan

A small C library, libspscan, does the scanning, BIP352 matching and the BIP158 filter checks.

It doesn't read or write anything and never sees a spend key. This allows other wallets can use it.

spscand needs Python 3.11, libsecp256k1 and a C compiler for libspscan. Nothing from PyPI.

Limits

• Only works with confirmed blocks, and mempool payments are not reported.
• A malicious BlindBit server could hide a payment by serving incomplete data.
• Filter mode P2P connections are unencrypted (no BIP324 yet). Onion peers are fine. Filter mode gains are marginal with hundreds of labels

That's enough yapping for me. Now let me enjoy my fish noodles