Commit Graph

3 Commits

Author SHA1 Message Date
Kgothatso Ngako
b4ac65f5c9 feat: sign a nostr event with the group's shared key
A ceremony leaves every member holding a share of a t-of-n key and no way
to use it. This is the other half: a session that turns an unsigned nostr
event into one signed by the group.

The shape is ChillDkgRitualManager's, deliberately. The member who
proposes coordinates, protocol messages travel as gift-wrapped rumors on
the same NIP-17 pipeline chat messages use, each inbound message is
persisted and then the session is asked whether it can move, and every
step is recomputed from stored inputs so a device killed mid-round
resumes on the next message. Anyone who has read that manager can read
this one.

    proposer --[ 30320 proposal   ]-> everyone   the unsigned event
    signer   --[ 30321 nonce      ]-> everyone   this device's public nonce
    proposer --[ 30322 signer set ]-> everyone   who signs, and their aggregated nonce
    signer   --[ 30323 partial    ]-> everyone   this device's partial signature
    proposer --[ 30324 signature  ]-> everyone   the finished 64-byte signature
    anyone   --[ 30325 failure    ]-> everyone   abandon + blame

Three things are genuinely different, and each is why this is a separate
manager rather than another branch of that one.

**It does not need everybody.** A DKG cannot finish until every member
takes part; that is what makes the key. Signing needs t, and waiting for
n would throw away the property the group ran a ceremony to get. So the
coordinator waits for the threshold to be reachable, picks a set and says
who is in it. Members left out do nothing and stall nothing.

**Restart-safety is forced rather than chosen.** SecretNonce cannot be
serialised and refuses to be used twice, so storing the randomness it
derives from and regenerating on demand is the only way a session
survives the app closing. That is safe for exactly one reason: a session
signs one message and cannot be made to sign another. Two rules hold it
in place and both are load-bearing rather than tidy:

  - the event id is written at creation, and a proposal that disagrees
    with it is refused rather than applied;
  - the aggregated nonce and signer set are write-once. A coordinator
    that sends a second, different set is ignored. Obeying it would mean
    two partial signatures over one secret nonce against two challenges,
    which is precisely how a secret share is extracted. The session
    stalls; the share does not.

**One approval, not three.** A DKG asks three times because each step
publishes something different and commits the member to something
different. Here every step serves one decision -- sign this event or do
not -- and the event is fixed before the member is asked, so a second
prompt would be the same question twice. Declining is broadcast rather
than silent: a t-of-n group can sign without you, but only if it knows.

Two things are checked rather than trusted, both because the coordinator
is untrusted by construction: the event id is recomputed from the
proposal's own fields, so a proposer cannot have the group sign one thing
while showing them another; and the finished signature is verified before
the session is called complete, so a bad aggregate is a failure here
rather than a rejection at every relay it reaches.

Signer ids are derived, not stored: a member's FROST id is their index in
the bytewise sort of the ceremony's host keys, the same ordering ChillDKG
hashed into the session identity and the same one the public shares are
in. Deriving means signing cannot disagree with the ceremony that made
the key.

DkgSession gains publicShares, kept because FROST validates each signer's
secret share against its public one. A ceremony finished before this
column reads back null and signing runs without that check rather than
refusing.

The tests run the same calls in the same order against real FROST and
assert the aggregate verifies as a nostr signature. That path was written
from reading the library rather than from a working example, so it is the
part most likely to be subtly wrong -- and wired up wrong it fails
silently, on every device.

Kinds start at 30320 with a gap. The DKG runs 30310-30316 and the
nip30303 document kinds run 30300 up; those two already collide at 30310
and 30311, and SubmissionEvent sits on 30312, which is also the DKG's
round-1 kind. They are kept apart today only by riding different
transports, which is luck. Signing shares a transport and rooms with the
DKG, so it starts clear of both.

No UI yet: this is the session logic, reachable through proposeSigning,
approve and decline.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-05 21:38:23 +02:00
Kgothatso Ngako
fcc28de931 Revert "fix: hold a payload whose parent has not arrived instead of losing the event"
This reverts commit d7aac49.

Reverting restores the defect it addressed: a payload referencing a row
the receiver does not have violates a foreign key, and SQLite aborts,
rolling back the whole inbound transaction -- the nostr event, the group
event, the submission and the transcript line, none of them retried.
That is what produced the observed `FOREIGN KEY constraint failed` on an
artifact whose dialect had not arrived.

Also drops the schema back to v5. Any device already migrated to v6 will
refuse to open its database, since the builder sets no destructive
fallback on downgrade; clear that app's data before installing a build
from this commit.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-05 21:12:50 +02:00
Kgothatso Ngako
d7aac49cf1 fix: hold a payload whose parent has not arrived instead of losing the event
A receiver hit `FOREIGN KEY constraint failed` on an artifact submission
and lost the whole group event. The artifact referenced a dialect the
receiver did not have, MantraArtifact.dialectId is a foreign key, and
SQLite answers a violated constraint by aborting -- which rolled back
the entire transaction the inbound pipeline runs in. Gone with it: the
NostrEvent, the MarmotGroupEvent, the submission's MarmotInnerEvent
holding the payload verbatim, and the transcript line. Nothing retries,
so the artifact stayed lost even once the dialect turned up.

Every nip30303 entity is a child of another and the schema enforces all
of it -- artifact→dialect, version→artifact, chapter→version,
chunk→chapter, translations→both of theirs -- so this was every branch,
not one.

And submissions make arriving before your parent ordinary rather than
exotic. That is the point of them: an admin submits a backlog in
whatever order they hold it, and a member who joined last week can be
sent what the group was told last month. Both produce payloads whose
parents are not here yet, and both were losing data.

So check the parents before inserting. A payload that arrives early is
held on the submission row -- awaitingEventId names what it waits for --
and applied when that arrives. Releasing one can release another, a
version freeing its chapters and those freeing their chunks, so it walks
outward until nothing more comes unstuck. A payload with a second parent
still missing is re-pointed at that one rather than retried on every
arrival.

Nothing is written to the transcript while a payload is held. Nobody has
said anything yet; the line appears when it is applied, in the position
its own timestamp gives it.

Two things fall out of the shape:

parentRefsOf is pure and separate from the lookups, because the mapping
is the part that can silently drift from the schema and there is no
database harness in commonTest to catch it. ParentRefsTest pins one case
per kind. Which table an id lives in is carried as the kind of event
that would have created it, so there is no second enum to keep in step.

applyInnerEvent takes ids rather than a GroupEvent, since replay happens
long after that object is gone. A released payload is recorded as not
ours: we hold the parents of anything we wrote, having written those too.

Also reconstructs a held bare nip30303 event from its own columns rather
than parsing its content as an event -- only submissions carry an event
there, and reading both that way would have stranded every bare one
permanently.

Verified: the v5→v6 migration runs clean on the receiver's real
populated database. The hold path itself still needs a fresh submission
from a sender to exercise end to end.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-05 21:05:35 +02:00