davideandClaude Sonnet 5.5
db24287ea5
The seed was the hash of the first block seen after the close, so a miner holding tickets
could withhold blocks until one made them win, the active Electrum server could pick which
real block was used by not announcing another (a failed corroboration even moved the draw to
the next block), and the participant order was the server-only `broadcast_at` with no
tie-break, so nobody could recompute the result.
- Open: every round gets a 32-byte `server_seed`, stored only Fernet-encrypted with the
master-xprv key (`server_seed_enc`), with its published `server_seed_hash`;
`draw_confirmations` is copied from round_config. The plaintext column is written only by
the reveal.
- Entering `drawing` (one transaction, `draw_committed` audit row): participants ordered by
bet txid, each `draw_position`, `participants_hash` (sha256 of `txid:vout:address\n`
lines; new `bet_vout`), `draw_height = tip_at_close + 1`. A tip of 0 keeps the round
`closing` (`draw_baseline_tip_unknown`, once per round). All persisted, so a resumed draw
reads rather than recomputes (the `_tick` branch itself is B-81).
- `_complete_draw` / `_wait_for_draw_block` replace `_wait_for_next_block`: wait for
`draw_confirmations` blocks from `draw_height`, then `ElectrumListener.agreed_block_hash`
asks every server, the active one included, for the header at that exact height (valid
work, >= 2 other answers, strict majority of all); no agreement means the same height is
asked again and `draw_header_corroboration_failed` is written once per distinct reported
hash. `draw_stalled` now counts from the last tip advance, or from when the quorum started
to fail. Seed = sha256(server_seed || block_hash || participants_hash), index = seed mod n.
- The winner, the seed and the reveal (`server_seed`, `winner_drawn` payload) are written in
one transaction; a round closing with no participants reveals too. A round opened before
this change (no commitment) is given a secret as it enters `drawing`.
- `GET /rounds/{id}/proof` (public, 404 `round_not_found`, translated in all 7 languages) and
the new fields on `GET /rounds/current`; `draw_confirmations` in `/admin/config` and the
/admin form; `server_seed_hash`/`draw_height` in `/admin/rounds`, never the secret.
- Alembic d3e8b15a7c42 (plain add_column / create_index, expression indexes untouched).
- Docs: the B-73 `*Stato:*`/`*Oggi:*` lines are gone, guides and CLAUDE.md describe the new
draw. Ambiguities resolved in api.md: the proof's participants also carry `amount_sats`
(RND-37 lists it); `seed` is decimal in the proof and hex in the audit row, as specified.
Tests changed because the spec changed: ElectrumListener.corroborate_header (asked only the
other servers about the block the active one announced) is replaced by agreed_block_hash and
its quorum tests ported; draw_winner takes the secret and the list fingerprint; the four
_wait_for_next_block scheduler tests are replaced by _wait_for_draw_block ones (fixed height,
confirmations, same-height retry, stall clock). New: test_draw_proof.py recomputes the winner
independently from the public proof, checks the plaintext secret is nowhere in the database,
the API or the log before the reveal, and that a second pass over a `drawing` round yields
the same winner. Mutation-checked: ordering by broadcast_at, an early reveal and asking the
tip instead of the draw height each fail tests.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
36 lines
2.6 KiB
Markdown
36 lines
2.6 KiB
Markdown
# ADR-07 — Ogni decisione che sposta denaro in base a una risposta di rete è corroborata da un quorum degli altri server configurati
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- **Stato:** Accettata
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- **Area:** Conferme e fiducia nella rete
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- **Fonte di verità per:** la scelta di progetto descritta qui sotto; i requisiti (`PREFISSO-NN`) che la attuano stanno nei documenti di dominio, indicati nelle *Conseguenze*.
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## Decisione
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**Ogni decisione che sposta denaro in base a una risposta di
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rete è corroborata da un quorum degli altri server configurati**: il blocco
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che semina l'estrazione, una moneta data per spesa all'esterno, un nuovo
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deposito da accreditare, il ripristino di una moneta, la conferma di una
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transazione (con prova merkle contro un header che possediamo), l'abbandono
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di una transazione, le monete del round verificate prima del pagamento. Si
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interrogano solo gli *altri* server, mai quello attivo (che è ciò che un
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attaccante controllerebbe); servono **almeno 2 risposte** e la maggioranza
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stretta di chi risponde. Il server rifiuta di partire con meno di 2 server
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di riserva, salvo `ALLOW_NO_QUORUM=true` (solo sviluppo). Se rispondono meno
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di 2 server, la corroborazione fallisce.
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- *Motivazione:* un solo server ostile non deve poter scegliere il
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vincitore (B-28), azzerare un saldo (B-29) o gonfiarlo (B-59), né far
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credere confermato un pagamento mai trasmesso (B-83). I saldi si muovono in
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entrambe le direzioni, quindi entrambe richiedono il quorum. Con 0 o 1
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server di riserva la «maggioranza» è una sola voce, o nessuna (B-84).
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- *Alternative scartate:* quorum facoltativo, che passa sempre con la lista
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vuota (la regola precedente: il default di `.env.example` spegneva ogni
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difesa senza avvisare).
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- *Conseguenze:* una corroborazione fallita **ritarda**, non perde e non
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libera fondi ([ADR-51](ADR-51-dubbio-liberano-mai-fondi.md)): il deposito è riproposto al refresh successivo,
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l'estrazione richiede di nuovo lo stesso blocco. Il quorum resta fra server
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scelti dall'operatore ([LIM-11]). Regole in
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[connessione-electrum.md](../connessione-electrum.md#5-il-quorum) (B-83, B-84).
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*Codice:* `app/electrum/listener.py:ElectrumListener._corroborate_majority` · `app/electrum/listener.py:ElectrumListener.agreed_block_hash` · `app/electrum/listener.py:ElectrumListener.corroborate_utxo_spent` · `app/electrum/listener.py:ElectrumListener.corroborate_utxo_credit` · `app/electrum/listener.py:ElectrumListener.corroborate_utxo_reinstatement` · `app/electrum/listener.py:ElectrumListener.confirmation_proven` · `app/main.py:lifespan` ·
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*Test:* `tests/unit/test_electrum_listener.py`, `tests/unit/test_confirmation_proof.py`
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