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>
poll_once marked a transaction confirmed on one server's `height > 0`, and
reinstate_reappeared_utxos restored a coin written off as spent outside the platform on
the active server's word alone, so a hostile active server could report a
never-relayed payout as confirmed (winner unpaid, round closed) or put a spent coin
back into a balance.
- electrum/merkle.py: pure merkle-branch verification against a block header.
- ElectrumListener.confirmation_proven(txid, height): the *other* servers are asked for
blockchain.transaction.get_merkle; a strict majority of at least the quorum minimum
must return a proof that recomputes to the merkle root of that block's header (block
height and position checked too). The header is the tip the listener holds, or for an
older block the one a majority of the quorum agrees on and that meets its own target;
a height above our tip cannot be proven. Quorum rules are _corroborate_majority's.
- poll_once takes the listener as `network`: the active server's history only nominates
a candidate (txid, height); the row confirms only when the proof holds, and stays
pending otherwise. With no network nothing confirms. ConfirmationPoller wires it.
- The reconciler's late-confirmation check of failed rows (B-78) now puts each claimed
(txid, height) to the same proof instead of counting histories.
- refresh_user splits reinstatement like a credit: find_reinstate_candidates (read-only;
same outpoint, recorded amount, confirmed) -> corroborate_utxo_reinstatement (same
quorum as a credit) -> reinstate_reappeared_utxos writes only what was corroborated,
rechecking the mark under the lock. Nothing is committed in the read phase any more.
- Broadcast fan-out, the third part of the finding, shipped with B-76.
Tests changed because the spec changed: every poll_once call now passes a network that
proves (FakeNetwork) — the confirmation tests are otherwise unchanged; the failed-row
"quorum does not confirm" test now asserts the claim goes to the proof.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
An empty ELECTRUM_FALLBACK_SERVERS (the .env.example default) silently made every
corroboration pass, and with fallbacks the majority was taken over whoever
answered, so one reachable fallback decided alone. TLS certificates were never
checked.
- _corroborate_majority passes only with at least 2 answers (MIN_QUORUM_RESPONSES)
and a strict majority of the answers; no other server configured, or fewer than
2 answering, fails. ALLOW_NO_QUORUM=true keeps the old reduced rule.
- config.validate_quorum_servers, called from the lifespan after parse_endpoints,
refuses to start with fewer than 2 fallback servers unless ALLOW_NO_QUORUM=true
(which logs a warning at every start).
- Optional pinning: `host:port[:mode]:pin=<sha256>` per fallback and
ELECTRUM_CERT_PIN for the primary; ElectrumClient compares the SHA-256 of the
DER certificate after the TLS handshake and a mismatch fails like an unreachable
server. A pin on a plaintext entry is a startup error.
- .env.example now ships the four bootstrap servers and documents both new
variables; docs/setup.md, spec, storico and BUGS.md updated.
- Tests changed because the spec changed: the two "no other servers configured ->
True" corroboration tests now assert that outcome only under allow_no_quorum.
Note: a dev .env with fewer than 2 fallback servers will now refuse to start.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
- Add docs/README.md as the index of all documentation.
- Split the 52 DEC entries of decisioni-e-limiti.md into docs/adr/ADR-NN
files (same numbers), add ADR-53 (audit log), TEMPLATE.md and an ADR index
with a feature -> ADR table.
- Rename decisioni-e-limiti.md to limiti-noti.md (LIM only) and rewrite all
DEC-nn references as links to the ADRs.
- Document the docs-first / SSOT / ADR rules in processo-di-modifica.md and
map the docs in CLAUDE.md and README.md.
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
davideandClaude Sonnet 5.5