Comment by narragansett | Hacker News Reader

Comment by narragansett | Hacker News Reader

It's a single Go binary, shaped like ssh. The main difference is the transport -- WebRTC instead of TCP -- so it doesn't need the machine to be reachable in the first place. Run "bitbang serve" and it prints a URL. Open it in a browser and you get a terminal, a file browser, and a proxy to web apps on that machine's network -- or connect from another terminal. There's nothing to install on the connecting side, no account, no port forwarding.

The trick to having no accounts: a device's identity is the hash of its public key, so browser and device verify each other directly. The server keeps no registry, authorizes nothing, and isn't in the data path -- it brokers the introduction and steps aside. About 75% of connections go direct P2P. The rest fall back to a TURN relay that only sees ciphertext. The server is open source and self-hostable -- and since it's out of the data path, cheap to run.

BitBang started on an ESP32, as the networking for a tiny telepresence robot. Embedded development is difficult and slow, so this CLI is where I've beaten the security model into shape. The embedded version is next. :)

Its really clever and minimal approach to getting (for my use case at least) the moral equivalent of a cloudflare tunnel without actually depending on CF. Super cool.

It is minimal and somewhat neat. It claims to be P2P, but it still needs to bootstrap the connection via central server. I think that always might be a limitation of P2P.

I had a similar idea but for wireguard only, where you would allow people to join a vpn through a "shared" jumpbox. To get started with wg is very simple, the problem is the same you need public IP address to scaffold everything.

Out of the two options I probably would prefer going wg route, just because it generalizes better. But this is a pretty cool demo of webrtc.

Right, bootstrapping needs a rendezvous point -- that's true of any P2P system, including the wg version. The difference is what the rendezvous knows and costs. Here it holds no accounts, no registry, and nothing that grants access, so it's a phonebook rather than a keyring, and it's out of the data path so it's cheap to run and you can self-host it.

On generalizing: wg wins for "put these machines on one network." WebRTC wins on reach, because the connecting side can be a browser -- a phone, a borrowed laptop, a machine you don't administer -- with nothing installed. A wg jumpbox still needs a client on both ends and a public IP for the box. Different tradeoff rather than a strictly better one.

If you are running this stuff on a cheap VPS with limited bandwidth, you will not want all of your traffic being routed as ingress and egress as that could easily eat your monthly bandwidth limit depending on the size of files and frequency.

> it still needs to bootstrap the connection via central server. I think that always might be a limitation of P2P

I think Iroh has a way of doing it using either DNS or BitTorrent DHT. Not perfect but fairly decentralized

Iroh's discovery is genuinely neat, and node-IDs-as-public-keys is similar to bitbang.

A browser can't join a DHT though because of no UDP sockets, so the connecting side would need a native client, which is the thing bitbang avoids. And DHT lets you locate the peer, but you still need somewhere to trade SDP and ICE candidates, so the rendezvous stays either way I think.

What I can do is keep the broker small enough that self-hosting is realistic, which is where it is now -- no accounts, no registry, nothing that grants access, only a simple broker.

Ah good point, no udp. I was looking at webtorrent but it does share the same limitation, unless you’re on the nodejs (non-browser) version.

Looking forward to trying bitbang! Seems super neat

I'm thrown off because you use so many em dashes, but the text surrounding them generally seems human.

Not judging or brigading, just personally don't want to add a new tool to my toolbelt knowing it's made with ai right now. Is bitbang made with ai?

There are several Coauthored by Claude commits. So at least partially LLM generated.

Yes, I started using AI for coding (Claude Code) after much consternation -- it's been really good at boosting my productivity. This is a passion project I tackle in my spare time, I like coding, but I don't like much of the coding. Much of it is drudgery-- AI is great for that. But there is no substitute for code review.

Gotcha. Thanks for the reply and I wish you success.

In case a direct p2p connection is not possible and it goes through the relay, is that for all traffic (even if encrypted )?

And who bears the cost for that (or does it have some FUP) (bandwidth cant be free/unlimited?)

Yes -- if direct P2P fails, everything rides the TURN relay that gets inserted automatically -- it's DTLS end-to-end so the relay only sees ciphertext, never plaintext or the access code.

On cost: I pay for it on bitba.ng and it's capped right now at 10 minutes per connection (mostly to prevent people from connecting and walking away). But you're not stuck with mine -- the signaling server is open source, so you can self-host and point it at your own TURN. The Python library supports "bring your own TURN" by specifying (--turn-url, --turn-user, --turn-credential); adding the same flags to the CLI is a small gap I need to close. There are TURN providers that have reasonably generous free tiers.

> There are TURN providers that have reasonably generous free tiers.

Could you provide a list of ones you know? Last I looked I wasn't able to find anything fast or reliable.

Cloudflare's is $0.05 per GB if your traffic exceeds the 1,000 GB free threshold.

Sounds like all I need to do is get this onto a machine and find a way to open the url click exploit or something and I get a RAT

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