# OnionWire threat model (v1)

OnionWire is a two-party chat over Tor onion services. There is no chat server.

## Tor relays are not a chat server

Each install hosts its own v3 onion and dials friends’ onions through in-process Arti. Relays move cells; they never see plaintext, never store messages, and never hold a roster. Compromising a relay is not compromising OnionWire’s message store. The store is the sqlite file on the endpoint.

## Location updates are not a missing-person finder

A signed `loc` frame (`onion`, `ts`, `sig`) rewrites a friend’s locator **only if** that friend is already in the roster, the signature verifies against the pinned pubkey, and `ts` is newer. There is no directory, DHT, or introduction server. If you rotated while they were offline, they cannot find you until they F3-paste your new invite. OnionWire will not hunt for a missing person.

## Rotating the onion does not revoke a friend

`F4` changes the locator only. The identity key is unchanged. Anyone who already has your pubkey can still prove they are talking to you, and a later invite paste with the same `k` updates their row. To become a new person, `/wipe-all` (new identity key). There is no in-band unfriend/revoke in v1.

## v1 stores plaintext locally

The message log, identity secret key, and friend public keys sit on disk unencrypted (aside from whatever the OS/FDE provides). A seized laptop yields the chat history and who you talk to. `/wipe` overwrites message bodies and vacuums; `/wipe-all` deletes the data dir. sqlcipher is out of v1.

## Fail closed

Peer onion down → send fails. Fingerprint mismatch vs the pinned key → hard fail, no send. Arti HS experimental: if it cannot publish, OnionWire stops; it does not fall back to C-tor.

## Profile is friend-visible, not a directory

A signed `prf` frame is shown to people who already have a session with you. Apply only for existing friends. There is still no name lookup, DHT, or public profile server. Anyone who already has a Noise session can see the profile you send them; that is not confidentiality against that friend.

## Monero sidecar is not a wallet

OnionWire never holds spend keys. Optional `ONIONWIRE_WALLET_RPC` talks HTTP to a user-hosted `monero-wallet-rpc`. Never trust a `rcp` frame without RPC confirmation (`verified` stays 0). Subaddress reuse is the user’s wallet policy.

## Backup file is the identity

`/backup` writes the identity and Noise static secrets. Treat the file like `onionwire.db`. Restore overwrites self keys and does **not** rewrite the friends table.

## Rate limit is availability, not anonymity

Incoming rendezvous accepts are token-bucket limited (30/60s, burst 10). Excess is dropped without handshake. That is a DoS/availability control. It does not hide that you run an onion, and it is not a traffic-analysis defense.

## Out of v1

Prosody, XMPP, s2s, MAM, carbons, outbox, multi-device, DHT / name server, sqlcipher.