Files
threshold/protocols/cmp/keygen/round5.go
zeekay bf88f5a56d round: pointer receivers on trivial round methods
VerifyMessage/StoreMessage/MessageContent/Number/BroadcastContent on
round structs were value receivers. Go FAQ: "if any method on T takes
*T, all methods should take *T." Finalize already takes *T (it mutates
round state) so the others should too. Aligns the method set, removes
silent struct-copies on every dispatch, and prevents future drift
where a value-receiver method accidentally observes pre-Finalize
state. No behavior change — all current methods are no-ops or return
constants.

Touched: round.Abort, round.Output, all CMP keygen/presign/sign rounds,
all Doerner keygen/sign rounds, all FROST keygen/sign rounds, xor
example. Build + vet clean; CMP/FROST/Doerner -race tests PASS.
2026-06-01 00:07:58 -07:00

90 lines
2.4 KiB
Go

package keygen
import (
"errors"
"github.com/luxfi/threshold/internal/round"
sch "github.com/luxfi/threshold/pkg/zk/sch"
"github.com/luxfi/threshold/protocols/cmp/config"
)
var _ round.Round = (*round5)(nil)
type round5 struct {
*round4
UpdatedConfig *config.Config
}
type broadcast5 struct {
round.NormalBroadcastContent
// SchnorrResponse is the Schnorr proof of knowledge of the new secret share
SchnorrResponse *sch.Response
}
// StoreBroadcastMessage implements round.BroadcastRound.
//
// - verify all Schnorr proof for the new ecdsa share.
func (r *round5) StoreBroadcastMessage(msg round.Message) error {
from := msg.From
body, ok := msg.Content.(*broadcast5)
if !ok || body == nil {
return round.ErrInvalidContent
}
if !body.SchnorrResponse.IsValid() {
return round.ErrNilFields
}
// Load Schnorr commitment from sync.Map
schnorrCommitValue, ok := r.SchnorrCommitments.Load(from)
if !ok {
return errors.New("schnorr commitment not found for party")
}
schnorrCommit, ok := schnorrCommitValue.(*sch.Commitment)
if !ok || schnorrCommit == nil {
return errors.New("invalid schnorr commitment for party")
}
// Check if public key exists for party
if r.UpdatedConfig == nil || r.UpdatedConfig.Public == nil {
return errors.New("updated config not initialized")
}
if _, ok := r.UpdatedConfig.Public[from]; !ok {
return errors.New("public key not found in updated config for party")
}
if !body.SchnorrResponse.Verify(r.HashForID(from),
r.UpdatedConfig.Public[from].ECDSA,
schnorrCommit, nil) {
return errors.New("failed to validate schnorr proof for received share")
}
return nil
}
// VerifyMessage implements round.Round.
func (*round5) VerifyMessage(round.Message) error { return nil }
// StoreMessage implements round.Round.
func (r *round5) StoreMessage(round.Message) error { return nil }
// Finalize implements round.Round.
func (r *round5) Finalize(chan<- *round.Message) (round.Session, error) {
return r.ResultRound(r.UpdatedConfig), nil
}
// MessageContent implements round.Round.
func (r *round5) MessageContent() round.Content { return nil }
// RoundNumber implements round.Content.
func (broadcast5) RoundNumber() round.Number { return 5 }
// BroadcastContent implements round.BroadcastRound.
func (r *round5) BroadcastContent() round.BroadcastContent {
return &broadcast5{
SchnorrResponse: sch.EmptyResponse(r.Group()),
}
}
// Number implements round.Round.
func (*round5) Number() round.Number { return 5 }