absolutebi/serai
1
0
Fork 0
mirror of https://github.com/serai-dex/serai.git synced 2025-12-08 12:19:24 +00:00
Code Issues Packages Projects Releases Wiki Activity

Handle the combination of DKG removals with re-attempts

Browse Source 
With a DKG removal comes a reduction in the amount of participants which was
ignored by re-attempts.

Now, we determine n/i based on the parties removed, and deterministically
obtain the context of who was removd.
This commit is contained in:
Luke Parker
2023-12-13 14:03:07 -05:00
parent 884b6a6fec
commit 77edd00725
15 changed files with 410 additions and 132 deletions
Download Patch File Download Diff File Expand all files Collapse all files

34
coordinator/src/main.rs
View File

@@ -108,14 +108,14 @@ async fn add_tributary<D: Db, Pro: Processors, P: P2p>(
// This is safe due to the message-queue deduplicating based off the intent system
let set = spec.set();
let our_i = spec
.i(Ristretto::generator() * key.deref())
.i(&[], Ristretto::generator() * key.deref())
.expect("adding a tributary for a set we aren't in set for");
processors
.send(
set.network,
processor_messages::key_gen::CoordinatorMessage::GenerateKey {
id: processor_messages::key_gen::KeyGenId { session: set.session, attempt: 0 },
params: frost::ThresholdParams::new(spec.t(), spec.n(), our_i.start).unwrap(),
params: frost::ThresholdParams::new(spec.t(), spec.n(&[]), our_i.start).unwrap(),
shares: u16::from(our_i.end) - u16::from(our_i.start),
},
)
@@ -370,21 +370,24 @@ async fn handle_processor_message<D: Db, P: P2p>(
signed: Transaction::empty_signed(),
}]
}
key_gen::ProcessorMessage::InvalidCommitments { id: _, faulty } => {
key_gen::ProcessorMessage::InvalidCommitments { id, faulty } => {
// This doesn't need the ID since it's a Provided transaction which everyone will provide
// With this provision comes explicit ordering (with regards to other RemoveParticipant
// transactions) and group consensus
// With this provision comes explicit ordering (with regards to other
// RemoveParticipantDueToDkg transactions) and group consensus
// Accordingly, this can't be replayed
// It could be included on-chain early/late with regards to the chain's active attempt,
// which attempt scheduling is written to avoid
vec![Transaction::RemoveParticipant(faulty)]
// which attempt scheduling is written to make a non-issue by auto re-attempting once a
// fatal slash occurs, regardless of timing
vec![Transaction::RemoveParticipantDueToDkg { attempt: id.attempt, participant: faulty }]
}
key_gen::ProcessorMessage::Shares { id, mut shares } => {
// Create a MuSig-based machine to inform Substrate of this key generation
let nonces = crate::tributary::dkg_confirmation_nonces(key, spec, &mut txn, id.attempt);
let removed = crate::tributary::removed_as_of_dkg_attempt(&txn, genesis, id.attempt)
.expect("participating in a DKG attempt yet we didn't track who was removed yet?");
let our_i = spec
.i(pub_key)
.i(&removed, pub_key)
.expect("processor message to DKG for a session we aren't a validator in");
// `tx_shares` needs to be done here as while it can be serialized from the HashMap
@@ -392,7 +395,7 @@ async fn handle_processor_message<D: Db, P: P2p>(
let mut tx_shares = Vec::with_capacity(shares.len());
for shares in &mut shares {
tx_shares.push(vec![]);
for i in 1 ..= spec.n() {
for i in 1 ..= spec.n(&removed) {
let i = Participant::new(i).unwrap();
if our_i.contains(&i) {
if shares.contains_key(&i) {
@@ -415,13 +418,16 @@ async fn handle_processor_message<D: Db, P: P2p>(
}
key_gen::ProcessorMessage::InvalidShare { id, accuser, faulty, blame } => {
// Check if the MuSig signature had any errors as if so, we need to provide
// RemoveParticipant
// RemoveParticipantDueToDkg
// As for the safety of calling error_generating_key_pair, the processor is presumed
// to only send InvalidShare or GeneratedKeyPair for a given attempt
let mut txs = if let Some(faulty) =
crate::tributary::error_generating_key_pair(&mut txn, key, spec, id.attempt)
{
vec![Transaction::RemoveParticipant(faulty)]
vec![Transaction::RemoveParticipantDueToDkg {
attempt: id.attempt,
participant: faulty,
}]
} else {
vec![]
};
@@ -457,14 +463,14 @@ async fn handle_processor_message<D: Db, P: P2p>(
}]
}
Err(p) => {
vec![Transaction::RemoveParticipant(p)]
vec![Transaction::RemoveParticipantDueToDkg { attempt: id.attempt, participant: p }]
}
}
}
// This is a response to the ordered VerifyBlame, which is why this satisfies the provided
// transaction's needs to be perfectly ordered
key_gen::ProcessorMessage::Blame { id: _, participant } => {
vec![Transaction::RemoveParticipant(participant)]
key_gen::ProcessorMessage::Blame { id, participant } => {
vec![Transaction::RemoveParticipantDueToDkg { attempt: id.attempt, participant }]
}
},
ProcessorMessage::Sign(msg) => match msg {