Corrects the architecture on two points raised in review, while the project
is still small enough to change cheaply.
1. Control and data are separated *logically*, not physically.
The old reading — "nothing but control may ride on iroh" — threw away iroh's
whole value and would have forced the data plane to reimplement STUN, ICE and
a relay. Now both planes ride on iroh with different ALPNs and different
connections, so the data plane inherits hole punching and relay fallback,
while proto/ still knows nothing about packets and dataplane/ knows nothing
about the control protocol.
New boundary: PacketTransport / PacketLink, an authenticated unreliable
datagram channel per (network, peer, protocol). tsunagi/data/1 runs the same
membership handshake, then DataOpen/DataOpenAck, then QUIC datagrams. Only
the smaller endpoint id dials, so exactly one link exists per pair.
A plugin is handed links and never learns reachability, so the WireGuard
announcement shrank to a public key: there is no address left to lie about.
2. WireGuard now runs in userspace, on boringtun's protocol state machine.
No kernel module, no wg tool, no ip shell-out, no loopback proxy: the wgtool,
backend and bridge modules are gone. Only creating a TUN device needs
privileges, and that sits behind TunFactory, so the entire data plane —
handshake, encryption, routing, address ownership — is tested with none.
Address ownership is enforced rather than believed: outbound packets go to
the owner of the destination address, inbound packets are dropped unless
their source is the address derived for the peer that sent them.
3. A `tsunagi` binary: secret, doctor, id, up. It owns the runtime, the
logging subscriber and Ctrl-C, which the library still refuses to.
Also fixes a reference cycle where IrohTransport held Arc<Inner>, which kept
the databases open and the directory lock held after shutdown; two storage
tests caught it once the cycle existed.
81 tests pass offline with no privileges, including real IPv6 packets
crossing a real WireGuard tunnel over real iroh connections. Verified by
hand: two CLI processes forming a mesh both on loopback and via n0 discovery
using only an endpoint id.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
tsunagiandClaude Opus 5
21be7e9b44