Module transport_ownership_proof 

TransportOwnershipProof — proving and verifying control of an announced address

Hashiverse peers announce themselves by address; before today, nothing in the announce wire format proved the announcer actually controlled that address. A peer with broken TLS / no cert could still announce, get into Kademlia, and pollute peer lists until every receiver independently RPCed it and pruned. The crate::protocol::payload::payload::AnnounceV2 variant fixes that by carrying an opaque proof byte blob next to peer_self; the receiver decides whether to admit the peer based on whether the proof verifies.

The shape of “a proof” depends on the transport. This module defines the interface; concrete impls live alongside each TransportServer:

• HTTPS transport (hashiverse-server-lib::HttpsTransportOwnershipProof): serialises the server’s current ACME-issued TLS chain plus a binding signature tying the chain to peer_self.id; verification is offline X.509 path validation against the bundled Mozilla NSS roots (see crate::tools::cert_validation::is_cert_valid) plus binding-signature check.
• Mem transport: an empty marker accepted by an empty-marker verifier; tests can exercise the V2 path end-to-end without real certs.

Wrong-transport mismatches surface naturally: if peer X sends bytes that transport Y’s verifier can’t deserialise, TransportOwnershipProof::prove returns false. No discriminator field needed on the wire.

TransportServer::get_transport_ownership_proof hands out one Arc<dyn TransportOwnershipProof> per server. The default trait impl returns a reject-all placeholder so old TransportServer impls keep compiling; real transports override it.

Structs

EmptyMarkerOwnershipProof

Empty-marker ownership proof, shared by transports that don’t (and can’t) cryptographically model address ownership: the in-memory test transport and the plain-TCP transport used for local-LAN / private-network deployments. Both ends agree on the empty byte string as the “I’m a trusted-network peer” token. An HTTPS-shaped proof byte blob sent to one of these servers fails the is_empty() check; conversely an empty-marker proof sent to an HTTPS server fails its postcard decode (or is_cert_valid on an empty chain). Cross-transport announces fall through naturally without a discriminator field on the wire.

RejectAllTransportOwnershipProof

Reject-all placeholder used as the default for TransportServer impls that haven’t been taught about ownership proofs yet (notably the wasm / TCP transports during the V2 rollout). It cannot produce a proof and rejects every inbound proof — safe by default: peers using this transport won’t be admitted to Kademlia via V2, and we never accidentally accept somebody else’s proof we don’t understand.

Traits

TransportOwnershipProof

A per-transport rule for producing our own proof bytes (announce-out) and verifying other peers’ proof bytes (announce-in). A single Arc<dyn TransportOwnershipProof> lives on a TransportServer and is used for both directions.