Improve P2P address book

[Boog900]

This is a tracking issue of things that should be improved in our P2P address book:

Don't replace addresses unless unreachable

We should not replace peers in either peer list (white or gray) unless they are unreachable, this should reduce an attackers ability to fill our peer list.

We should set up a task that periodically pulls unused peers from either the gray or white lists and attempts to ping them to see if they are reachable. If they are not we will keep them removed from the address book. When a new addresses come in they should only be added if there is space in the address book.

The function to ping peers:

cuprate/p2p/p2p-core/src/client/handshaker.rs

Line 195 in 4653ac5

pub async fn ping<N: NetworkZone>(addr: N::Addr) -> Result<u64, HandshakeError> {

Bucket addresses

We should use a bucket system like Bitcoin to store our p2p address, so that we guarantee a more diverse range of addresses.

Persist banned peers

Currently banned peers are forgotten on restarts, we should keep them in the p2p_store.

The functions where the peer filer is saved and loaded:

cuprate/p2p/address-book/src/store.rs

Lines 24 to 55 in 4653ac5

	pub fn save_peers_to_disk<Z: BorshNetworkZone>(
	cfg: &AddressBookConfig,
	white_list: &PeerList<Z>,
	gray_list: &PeerList<Z>,
	) -> JoinHandle<std::io::Result<()>> {
	// maybe move this to another thread but that would require cloning the data ... this
	// happens so infrequently that it's probably not worth it.
	let data = to_vec(&SerPeerDataV1 {
	white_list: white_list.peers.values().collect::<Vec<_>>(),
	gray_list: gray_list.peers.values().collect::<Vec<_>>(),
	})
	.unwrap();
	let file = cfg.peer_store_file.clone();
	spawn_blocking(move || fs::write(&file, &data))
	}
	pub async fn read_peers_from_disk<Z: BorshNetworkZone>(
	cfg: &AddressBookConfig,
	) -> Result<
	(
	Vec<ZoneSpecificPeerListEntryBase<Z::Addr>>,
	Vec<ZoneSpecificPeerListEntryBase<Z::Addr>>,
	),
	std::io::Error,
	> {
	let file = cfg.peer_store_file.clone();
	let data = spawn_blocking(move || fs::read(file)).await.unwrap()?;
	let de_ser: DeserPeerDataV1<Z::Addr> = from_slice(&data)?;
	Ok((de_ser.white_list, de_ser.gray_list))
	}

These functions should be changed to allow the ban list to be stored as well:

cuprate/p2p/address-book/src/book.rs

Line 63 in 4653ac5

banned_peers: HashMap<<Z::Addr as NetZoneAddress>::BanID, Instant>,

Properly implement an anchor system

TODO

[willco-1]

i'll take a shot at this!

[SyntheticBird45]

Heyo @willco-1 are you still working on persistent ban list ?