/
states.go
742 lines (599 loc) · 19.3 KB
/
states.go
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package gjkr
import (
"context"
"github.com/keep-network/keep-core/pkg/net"
"github.com/keep-network/keep-core/pkg/protocol/group"
"github.com/keep-network/keep-core/pkg/protocol/state"
)
type keyGenerationState = state.SyncState
const (
silentStateDelayBlocks = 0
silentStateActiveBlocks = 0
ephemeralKeyPairStateDelayBlocks = 1
ephemeralKeyPairStateActiveBlocks = 5
commitmentStateDelayBlocks = 1
commitmentStateActiveBlocks = 5
commitmentVerificationStateDelayBlocks = 1
commitmentVerificationStateActiveBlocks = 10
pointsShareStateDelayBlocks = 1
pointsShareStateActiveBlocks = 5
pointsValidationStateDelayBlocks = 1
pointsValidationStateActiveBlocks = 10
keyRevealStateDelayBlocks = 1
keyRevealStateActiveBlocks = 5
combinationStateDelayBlocks = 0
combinationStateActiveBlocks = 20
)
// ProtocolBlocks returns the total number of blocks it takes to execute
// all the required work defined by the GJKR protocol.
func ProtocolBlocks() uint64 {
return ephemeralKeyPairStateDelayBlocks +
ephemeralKeyPairStateActiveBlocks +
commitmentStateDelayBlocks +
commitmentStateActiveBlocks +
commitmentVerificationStateDelayBlocks +
commitmentVerificationStateActiveBlocks +
pointsShareStateDelayBlocks +
pointsShareStateActiveBlocks +
pointsValidationStateDelayBlocks +
pointsValidationStateActiveBlocks +
keyRevealStateDelayBlocks +
keyRevealStateActiveBlocks +
combinationStateDelayBlocks +
combinationStateActiveBlocks
}
// ephemeralKeyPairGenerationState is the state during which members broadcast
// public ephemeral keys generated for other members of the group.
// `EphemeralPublicKeyMessage`s are valid in this state.
//
// State covers phase 1 of the protocol.
type ephemeralKeyPairGenerationState struct {
channel net.BroadcastChannel
member *EphemeralKeyPairGeneratingMember
phaseMessages []*EphemeralPublicKeyMessage
}
func (ekpgs *ephemeralKeyPairGenerationState) DelayBlocks() uint64 {
return ephemeralKeyPairStateDelayBlocks
}
func (ekpgs *ephemeralKeyPairGenerationState) ActiveBlocks() uint64 {
return ephemeralKeyPairStateActiveBlocks
}
func (ekpgs *ephemeralKeyPairGenerationState) Initiate(ctx context.Context) error {
message, err := ekpgs.member.GenerateEphemeralKeyPair()
if err != nil {
return err
}
if err := ekpgs.channel.Send(ctx, message); err != nil {
return err
}
return nil
}
func (ekpgs *ephemeralKeyPairGenerationState) Receive(msg net.Message) error {
switch phaseMessage := msg.Payload().(type) {
case *EphemeralPublicKeyMessage:
if ekpgs.member.shouldAcceptMessage(
phaseMessage.SenderID(),
msg.SenderPublicKey(),
) && ekpgs.member.sessionID == phaseMessage.sessionID {
ekpgs.phaseMessages = append(ekpgs.phaseMessages, phaseMessage)
}
}
return nil
}
func (ekpgs *ephemeralKeyPairGenerationState) Next() (state.SyncState, error) {
return &symmetricKeyGenerationState{
channel: ekpgs.channel,
member: ekpgs.member.InitializeSymmetricKeyGeneration(),
previousPhaseMessages: ekpgs.phaseMessages,
}, nil
}
func (ekpgs *ephemeralKeyPairGenerationState) MemberIndex() group.MemberIndex {
return ekpgs.member.ID
}
// symmetricKeyGenerationState is the state during which members compute
// symmetric keys from the previously exchanged ephemeral public keys.
// No messages are valid in this state.
//
// State covers phase 2 of the protocol.
type symmetricKeyGenerationState struct {
channel net.BroadcastChannel
member *SymmetricKeyGeneratingMember
previousPhaseMessages []*EphemeralPublicKeyMessage
}
func (skgs *symmetricKeyGenerationState) DelayBlocks() uint64 {
return silentStateDelayBlocks
}
func (skgs *symmetricKeyGenerationState) ActiveBlocks() uint64 {
return silentStateActiveBlocks
}
func (skgs *symmetricKeyGenerationState) Initiate(ctx context.Context) error {
skgs.member.MarkInactiveMembers(skgs.previousPhaseMessages)
return skgs.member.GenerateSymmetricKeys(skgs.previousPhaseMessages)
}
func (skgs *symmetricKeyGenerationState) Receive(msg net.Message) error {
return nil
}
func (skgs *symmetricKeyGenerationState) Next() (state.SyncState, error) {
return &commitmentState{
channel: skgs.channel,
member: skgs.member.InitializeCommitting(),
}, nil
}
func (skgs *symmetricKeyGenerationState) MemberIndex() group.MemberIndex {
return skgs.member.ID
}
// commitmentState is the state during which members compute their individual
// shares and commitments to those shares. Two messages are valid in this state:
// - `PeerSharesMessage`
// - `MemberCommitmentsMessage`
//
// State covers phase 3 of the protocol.
type commitmentState struct {
channel net.BroadcastChannel
member *CommittingMember
phaseSharesMessages []*PeerSharesMessage
phaseCommitmentsMessages []*MemberCommitmentsMessage
}
func (cs *commitmentState) DelayBlocks() uint64 {
return commitmentStateDelayBlocks
}
func (cs *commitmentState) ActiveBlocks() uint64 {
return commitmentStateActiveBlocks
}
func (cs *commitmentState) Initiate(ctx context.Context) error {
sharesMsg, commitmentsMsg, err := cs.member.CalculateMembersSharesAndCommitments()
if err != nil {
return err
}
if err := cs.channel.Send(ctx, sharesMsg); err != nil {
return err
}
if err := cs.channel.Send(ctx, commitmentsMsg); err != nil {
return err
}
return nil
}
func (cs *commitmentState) Receive(msg net.Message) error {
switch phaseMessage := msg.Payload().(type) {
case *PeerSharesMessage:
if cs.member.shouldAcceptMessage(
phaseMessage.SenderID(),
msg.SenderPublicKey(),
) && cs.member.sessionID == phaseMessage.sessionID {
cs.phaseSharesMessages = append(cs.phaseSharesMessages, phaseMessage)
}
case *MemberCommitmentsMessage:
if cs.member.shouldAcceptMessage(
phaseMessage.SenderID(),
msg.SenderPublicKey(),
) && cs.member.sessionID == phaseMessage.sessionID {
cs.phaseCommitmentsMessages = append(
cs.phaseCommitmentsMessages,
phaseMessage,
)
}
}
return nil
}
func (cs *commitmentState) Next() (state.SyncState, error) {
return &commitmentsVerificationState{
channel: cs.channel,
member: cs.member.InitializeCommitmentsVerification(),
previousPhaseSharesMessages: cs.phaseSharesMessages,
previousPhaseCommitmentsMessages: cs.phaseCommitmentsMessages,
}, nil
}
func (cs *commitmentState) MemberIndex() group.MemberIndex {
return cs.member.ID
}
// commitmentsVerificationState is the state during which members validate
// shares and commitments computed and published by other members in the
// previous phase. `SecretShareAccusationMessage`s are valid in this state.
//
// State covers phase 4 of the protocol.
type commitmentsVerificationState struct {
channel net.BroadcastChannel
member *CommitmentsVerifyingMember
previousPhaseSharesMessages []*PeerSharesMessage
previousPhaseCommitmentsMessages []*MemberCommitmentsMessage
phaseAccusationsMessages []*SecretSharesAccusationsMessage
}
func (cvs *commitmentsVerificationState) DelayBlocks() uint64 {
return commitmentVerificationStateDelayBlocks
}
func (cvs *commitmentsVerificationState) ActiveBlocks() uint64 {
return commitmentVerificationStateActiveBlocks
}
func (cvs *commitmentsVerificationState) Initiate(ctx context.Context) error {
cvs.member.MarkInactiveMembers(
cvs.previousPhaseSharesMessages,
cvs.previousPhaseCommitmentsMessages,
)
accusationsMsg, err := cvs.member.VerifyReceivedSharesAndCommitmentsMessages(
cvs.previousPhaseSharesMessages,
cvs.previousPhaseCommitmentsMessages,
)
if err != nil {
return err
}
if err := cvs.channel.Send(ctx, accusationsMsg); err != nil {
return err
}
return nil
}
func (cvs *commitmentsVerificationState) Receive(msg net.Message) error {
switch phaseMessage := msg.Payload().(type) {
case *SecretSharesAccusationsMessage:
if cvs.member.shouldAcceptMessage(
phaseMessage.SenderID(),
msg.SenderPublicKey(),
) && cvs.member.sessionID == phaseMessage.sessionID {
cvs.phaseAccusationsMessages = append(
cvs.phaseAccusationsMessages,
phaseMessage,
)
}
}
return nil
}
func (cvs *commitmentsVerificationState) Next() (state.SyncState, error) {
return &sharesJustificationState{
channel: cvs.channel,
member: cvs.member.InitializeSharesJustification(),
previousPhaseAccusationsMessages: cvs.phaseAccusationsMessages,
}, nil
}
func (cvs *commitmentsVerificationState) MemberIndex() group.MemberIndex {
return cvs.member.ID
}
// sharesJustificationState is the state during which members resolve
// accusations published by other group members in the previous state.
// No messages are valid in this state.
//
// State covers phase 5 of the protocol.
type sharesJustificationState struct {
channel net.BroadcastChannel
member *SharesJustifyingMember
previousPhaseAccusationsMessages []*SecretSharesAccusationsMessage
}
func (sjs *sharesJustificationState) DelayBlocks() uint64 {
return silentStateDelayBlocks
}
func (sjs *sharesJustificationState) ActiveBlocks() uint64 {
return silentStateActiveBlocks
}
func (sjs *sharesJustificationState) Initiate(ctx context.Context) error {
sjs.member.MarkInactiveMembers(sjs.previousPhaseAccusationsMessages)
err := sjs.member.ResolveSecretSharesAccusationsMessages(
sjs.previousPhaseAccusationsMessages,
)
if err != nil {
return err
}
return nil
}
func (sjs *sharesJustificationState) Receive(msg net.Message) error {
return nil
}
func (sjs *sharesJustificationState) Next() (state.SyncState, error) {
return &qualificationState{
channel: sjs.channel,
member: sjs.member.InitializeQualified(),
}, nil
}
func (sjs *sharesJustificationState) MemberIndex() group.MemberIndex {
return sjs.member.ID
}
// qualificationState is the state during which group members combine all valid
// secret shares published by other group members in the previous states.
// No messages are valid in this state.
//
// State covers phase 6 of the protocol.
type qualificationState struct {
channel net.BroadcastChannel
member *QualifiedMember
}
func (qs *qualificationState) DelayBlocks() uint64 {
return silentStateDelayBlocks
}
func (qs *qualificationState) ActiveBlocks() uint64 {
return silentStateActiveBlocks
}
func (qs *qualificationState) Initiate(ctx context.Context) error {
qs.member.CombineMemberShares()
return nil
}
func (qs *qualificationState) Receive(msg net.Message) error {
return nil
}
func (qs *qualificationState) Next() (state.SyncState, error) {
return &pointsShareState{
channel: qs.channel,
member: qs.member.InitializeSharing(),
}, nil
}
func (qs *qualificationState) MemberIndex() group.MemberIndex {
return qs.member.ID
}
// pointsShareState is the state during which group members calculate and
// publish their public key share points.
// `MemberPublicKeySharePointsMessage`s are valid in this state.
//
// State covers phase 7 of the protocol.
type pointsShareState struct {
channel net.BroadcastChannel
member *SharingMember // TODO: SharingMember should be renamed to PointsSharingMember
phaseMessages []*MemberPublicKeySharePointsMessage
}
func (pss *pointsShareState) DelayBlocks() uint64 {
return pointsShareStateDelayBlocks
}
func (pss *pointsShareState) ActiveBlocks() uint64 {
return pointsShareStateActiveBlocks
}
func (pss *pointsShareState) Initiate(ctx context.Context) error {
message := pss.member.CalculatePublicKeySharePoints()
if err := pss.channel.Send(ctx, message); err != nil {
return err
}
return nil
}
func (pss *pointsShareState) Receive(msg net.Message) error {
switch phaseMessage := msg.Payload().(type) {
case *MemberPublicKeySharePointsMessage:
if pss.member.shouldAcceptMessage(
phaseMessage.SenderID(),
msg.SenderPublicKey(),
) && pss.member.sessionID == phaseMessage.sessionID {
pss.phaseMessages = append(pss.phaseMessages, phaseMessage)
}
}
return nil
}
func (pss *pointsShareState) Next() (state.SyncState, error) {
return &pointsValidationState{
channel: pss.channel,
member: pss.member,
previousPhaseMessages: pss.phaseMessages,
}, nil
}
func (pss *pointsShareState) MemberIndex() group.MemberIndex {
return pss.member.ID
}
// pointsValidationState is the state during which group members validate
// public key share points published by other group members in the previous
// state. `PointsAccusationsMessage`s are valid in this state.
//
// State covers phase 8 of the protocol.
type pointsValidationState struct {
channel net.BroadcastChannel
member *SharingMember // TODO: split validation logic into PointsValidatingMember
previousPhaseMessages []*MemberPublicKeySharePointsMessage
phaseMessages []*PointsAccusationsMessage
}
func (pvs *pointsValidationState) DelayBlocks() uint64 {
return pointsValidationStateDelayBlocks
}
func (pvs *pointsValidationState) ActiveBlocks() uint64 {
return pointsValidationStateActiveBlocks
}
func (pvs *pointsValidationState) Initiate(ctx context.Context) error {
pvs.member.MarkInactiveMembers(pvs.previousPhaseMessages)
accusationMsg, err := pvs.member.VerifyPublicKeySharePoints(
pvs.previousPhaseMessages,
)
if err != nil {
return err
}
if err := pvs.channel.Send(ctx, accusationMsg); err != nil {
return err
}
return nil
}
func (pvs *pointsValidationState) Receive(msg net.Message) error {
switch phaseMessage := msg.Payload().(type) {
case *PointsAccusationsMessage:
if pvs.member.shouldAcceptMessage(
phaseMessage.SenderID(),
msg.SenderPublicKey(),
) && pvs.member.sessionID == phaseMessage.sessionID {
pvs.phaseMessages = append(pvs.phaseMessages, phaseMessage)
}
}
return nil
}
func (pvs *pointsValidationState) Next() (state.SyncState, error) {
return &pointsJustificationState{
channel: pvs.channel,
member: pvs.member.InitializePointsJustification(),
previousPhaseMessages: pvs.phaseMessages,
}, nil
}
func (pvs *pointsValidationState) MemberIndex() group.MemberIndex {
return pvs.member.ID
}
// pointsJustificationState is the state during which group members resolve
// accusations published by other group members in the previous state.
// No messages are valid in this state.
//
// State covers phase 9 of the protocol.
type pointsJustificationState struct {
channel net.BroadcastChannel
member *PointsJustifyingMember
previousPhaseMessages []*PointsAccusationsMessage
}
func (pjs *pointsJustificationState) DelayBlocks() uint64 {
return silentStateDelayBlocks
}
func (pjs *pointsJustificationState) ActiveBlocks() uint64 {
return silentStateActiveBlocks
}
func (pjs *pointsJustificationState) Initiate(ctx context.Context) error {
pjs.member.MarkInactiveMembers(pjs.previousPhaseMessages)
err := pjs.member.ResolvePublicKeySharePointsAccusationsMessages(
pjs.previousPhaseMessages,
)
if err != nil {
return err
}
return nil
}
func (pjs *pointsJustificationState) Receive(msg net.Message) error {
return nil
}
func (pjs *pointsJustificationState) Next() (state.SyncState, error) {
return &keyRevealState{
channel: pjs.channel,
member: pjs.member.InitializeRevealing(),
}, nil
}
func (pjs *pointsJustificationState) MemberIndex() group.MemberIndex {
return pjs.member.ID
}
// keyRevealState is the state during which group members reveal ephemeral
// private keys used to create an ephemeral symmetric keys with disqualified
// members who share a group private key.
//
// State covers phase 10 of the protocol.
type keyRevealState struct {
channel net.BroadcastChannel
member *RevealingMember // TODO: Rename to KeyRevealingMember
phaseMessages []*MisbehavedEphemeralKeysMessage
}
func (rs *keyRevealState) DelayBlocks() uint64 {
return keyRevealStateDelayBlocks
}
func (rs *keyRevealState) ActiveBlocks() uint64 {
return keyRevealStateActiveBlocks
}
func (rs *keyRevealState) Initiate(ctx context.Context) error {
revealMsg, err := rs.member.RevealMisbehavedMembersKeys()
if err != nil {
return err
}
if err := rs.channel.Send(ctx, revealMsg); err != nil {
return err
}
return nil
}
func (rs *keyRevealState) Receive(msg net.Message) error {
switch phaseMessage := msg.Payload().(type) {
case *MisbehavedEphemeralKeysMessage:
if rs.member.shouldAcceptMessage(
phaseMessage.SenderID(),
msg.SenderPublicKey(),
) && rs.member.sessionID == phaseMessage.sessionID {
rs.phaseMessages = append(rs.phaseMessages, phaseMessage)
}
}
return nil
}
func (rs *keyRevealState) Next() (state.SyncState, error) {
return &reconstructionState{
channel: rs.channel,
member: rs.member.InitializeReconstruction(),
previousPhaseMessages: rs.phaseMessages,
}, nil
}
func (rs *keyRevealState) MemberIndex() group.MemberIndex {
return rs.member.ID
}
// reconstructionState is the state during which group members reconstruct
// individual keys of members disqualified in previous states. No messages are
// valid in this state.
//
// State covers phase 11 of the protocol.
type reconstructionState struct {
channel net.BroadcastChannel
member *ReconstructingMember
previousPhaseMessages []*MisbehavedEphemeralKeysMessage
}
func (rs *reconstructionState) DelayBlocks() uint64 {
return silentStateDelayBlocks
}
func (rs *reconstructionState) ActiveBlocks() uint64 {
return silentStateActiveBlocks
}
func (rs *reconstructionState) Initiate(ctx context.Context) error {
rs.member.MarkInactiveMembers(rs.previousPhaseMessages)
if err := rs.member.ReconstructMisbehavedIndividualKeys(
rs.previousPhaseMessages,
); err != nil {
return err
}
return nil
}
func (rs *reconstructionState) Receive(msg net.Message) error {
return nil
}
func (rs *reconstructionState) Next() (state.SyncState, error) {
return &combinationState{
channel: rs.channel,
member: rs.member.InitializeCombining(),
}, nil
}
func (rs *reconstructionState) MemberIndex() group.MemberIndex {
return rs.member.ID
}
// combinationState is the state during which group members combine together all
// qualified key shares to form a group public key. No messages are valid in
// this state.
//
// State covers phase 12 of the protocol.
type combinationState struct {
channel net.BroadcastChannel
member *CombiningMember
}
func (cs *combinationState) DelayBlocks() uint64 {
return combinationStateDelayBlocks
}
func (cs *combinationState) ActiveBlocks() uint64 {
return combinationStateActiveBlocks
}
func (cs *combinationState) Initiate(ctx context.Context) error {
cs.member.ComputeGroupPublicKeyShares()
cs.member.CombineGroupPublicKey()
return nil
}
func (cs *combinationState) Receive(msg net.Message) error {
return nil
}
func (cs *combinationState) Next() (state.SyncState, error) {
return &finalizationState{
channel: cs.channel,
member: cs.member.InitializeFinalization(),
}, nil
}
func (cs *combinationState) MemberIndex() group.MemberIndex {
return cs.member.ID
}
// finalizationState is the last state of GJKR DKG protocol - in this state,
// distributed key generation is completed. No messages are valid in this state.
//
// State prepares a result to publish in phase 13 of the protocol but it does
// not execute that phase.
type finalizationState struct {
channel net.BroadcastChannel
member *FinalizingMember
}
func (fs *finalizationState) DelayBlocks() uint64 {
return silentStateDelayBlocks
}
func (fs *finalizationState) ActiveBlocks() uint64 {
return silentStateActiveBlocks
}
func (fs *finalizationState) Initiate(ctx context.Context) error {
return nil
}
func (fs *finalizationState) Receive(msg net.Message) error {
return nil
}
func (fs *finalizationState) Next() (state.SyncState, error) {
return nil, nil
}
func (fs *finalizationState) MemberIndex() group.MemberIndex {
return fs.member.ID
}
func (fs *finalizationState) result() *Result {
return fs.member.Result()
}