path: root/dex/governance.go

package dex

import (
    "context"
    "crypto/ecdsa"
    "math/big"
    "time"

    coreCommon "github.com/dexon-foundation/dexon-consensus-core/common"
    coreCrypto "github.com/dexon-foundation/dexon-consensus-core/core/crypto"
    coreEcdsa "github.com/dexon-foundation/dexon-consensus-core/core/crypto/ecdsa"
    coreTypes "github.com/dexon-foundation/dexon-consensus-core/core/types"
    "github.com/dexon-foundation/dexon/common"
    "github.com/dexon-foundation/dexon/core/types"
    "github.com/dexon-foundation/dexon/core/vm"
    "github.com/dexon-foundation/dexon/crypto"
    "github.com/dexon-foundation/dexon/log"
    "github.com/dexon-foundation/dexon/params"
    "github.com/dexon-foundation/dexon/rlp"
    "github.com/dexon-foundation/dexon/rpc"
)

type DexconGovernance struct {
    b           *DexAPIBackend
    chainConfig *params.ChainConfig
    privateKey  *ecdsa.PrivateKey
    address     common.Address
}

// NewDexconGovernance retruns a governance implementation of the DEXON
// consensus governance interface.
func NewDexconGovernance(backend *DexAPIBackend, chainConfig *params.ChainConfig,
    privKey *ecdsa.PrivateKey) *DexconGovernance {
    return &DexconGovernance{
        b:           backend,
        chainConfig: chainConfig,
        privateKey:  privKey,
        address:     crypto.PubkeyToAddress(privKey.PublicKey),
    }
}

func (d *DexconGovernance) getRoundHeight(ctx context.Context, round uint64) (uint64, error) {
    state, _, err := d.b.StateAndHeaderByNumber(ctx, rpc.LatestBlockNumber)
    if state == nil || err != nil {
        return 0, err
    }
    s := vm.GovernanceStateHelper{state}
    return s.RoundHeight(big.NewInt(int64(round))).Uint64(), nil
}

func (d *DexconGovernance) getGovState() *vm.GovernanceStateHelper {
    ctx := context.Background()
    state, _, err := d.b.StateAndHeaderByNumber(ctx, rpc.LatestBlockNumber)
    if state == nil || err != nil {
        return nil
    }

    return &vm.GovernanceStateHelper{state}
}

func (d *DexconGovernance) getGovStateAtRound(round uint64) *vm.GovernanceStateHelper {
    ctx := context.Background()
    blockHeight, err := d.getRoundHeight(ctx, round)
    if err != nil {
        return nil
    }

    state, _, err := d.b.StateAndHeaderByNumber(ctx, rpc.BlockNumber(blockHeight))
    if state == nil || err != nil {
        return nil
    }

    return &vm.GovernanceStateHelper{state}
}

// Configuration return the total ordering K constant.
func (d *DexconGovernance) Configuration(round uint64) *coreTypes.Config {
    s := d.getGovStateAtRound(round)
    c := s.Configuration()

    return &coreTypes.Config{
        NumChains:        c.NumChains,
        LambdaBA:         time.Duration(c.LambdaBA) * time.Millisecond,
        LambdaDKG:        time.Duration(c.LambdaDKG) * time.Millisecond,
        K:                c.K,
        PhiRatio:         c.PhiRatio,
        NotarySetSize:    c.NotarySetSize,
        DKGSetSize:       c.DKGSetSize,
        RoundInterval:    time.Duration(c.RoundInterval) * time.Millisecond,
        MinBlockInterval: time.Duration(c.MinBlockInterval) * time.Millisecond,
        MaxBlockInterval: time.Duration(c.MaxBlockInterval) * time.Millisecond,
    }
}

// CRS returns the CRS for a given round.
func (d *DexconGovernance) CRS(round uint64) coreCommon.Hash {
    s := d.getGovStateAtRound(round)
    return coreCommon.Hash(s.CRS(big.NewInt(int64(round))))
}

// ProposeCRS send proposals of a new CRS
func (d *DexconGovernance) ProposeCRS(signedCRS []byte) {
    method := vm.GovernanceContractName2Method["proposeCRS"]

    res, err := method.Inputs.Pack(signedCRS)
    if err != nil {
        log.Error("failed to pack proposeCRS input: %s", err)
        return
    }

    data := append(method.Id(), res...)
    err = d.sendGovTx(context.Background(), data)
    if err != nil {
        log.Error("failed to send proposeCRS tx: %s", err)
    }
}

// NodeSet returns the current notary set.
func (d *DexconGovernance) NodeSet(round uint64) []coreCrypto.PublicKey {
    s := d.getGovStateAtRound(round)
    var pks []coreCrypto.PublicKey

    for _, n := range s.Nodes() {
        pks = append(pks, coreEcdsa.NewPublicKeyFromByteSlice(n.PublicKey))
    }
    return pks
}

func (d *DexconGovernance) sendGovTx(ctx context.Context, data []byte) error {
    gasPrice, err := d.b.SuggestPrice(ctx)
    if err != nil {
        return err
    }

    nonce, err := d.b.GetPoolNonce(ctx, d.address)
    if err != nil {
        return err
    }

    tx := types.NewTransaction(
        nonce,
        vm.GovernanceContractAddress,
        big.NewInt(0),
        uint64(200000),
        gasPrice,
        data)

    signer := types.NewEIP155Signer(d.chainConfig.ChainID)

    tx, err = types.SignTx(tx, signer, d.privateKey)
    if err != nil {
        return err
    }
    return d.b.SendTx(ctx, tx)
}

// NotifyRoundHeight register the mapping between round and height.
func (d *DexconGovernance) NotifyRoundHeight(targetRound, consensusHeight uint64) {
    method := vm.GovernanceContractName2Method["snapshotRound"]

    res, err := method.Inputs.Pack(
        big.NewInt(int64(targetRound)), big.NewInt(int64(consensusHeight)))
    if err != nil {
        log.Error("failed to pack snapshotRound input: %s", err)
        return
    }

    data := append(method.Id(), res...)
    err = d.sendGovTx(context.Background(), data)
    if err != nil {
        log.Error("failed to send snapshotRound tx: %s", err)
    }
}

// AddDKGComplaint adds a DKGComplaint.
func (d *DexconGovernance) AddDKGComplaint(round uint64, complaint *coreTypes.DKGComplaint) {
    method := vm.GovernanceContractName2Method["addDKGComplaint"]

    encoded, err := rlp.EncodeToBytes(complaint)
    if err != nil {
        log.Error("failed to RLP encode complaint to bytes: %s", err)
        return
    }

    res, err := method.Inputs.Pack(big.NewInt(int64(round)), encoded)
    if err != nil {
        log.Error("failed to pack addDKGComplaint input: %s", err)
        return
    }

    data := append(method.Id(), res...)
    err = d.sendGovTx(context.Background(), data)
    if err != nil {
        log.Error("failed to send addDKGComplaint tx: %s", err)
    }
}

// DKGComplaints gets all the DKGComplaints of round.
func (d *DexconGovernance) DKGComplaints(round uint64) []*coreTypes.DKGComplaint {
    s := d.getGovState()
    var dkgComplaints []*coreTypes.DKGComplaint
    for _, pk := range s.DKGMasterPublicKeys(big.NewInt(int64(round))) {
        x := new(coreTypes.DKGComplaint)
        if err := rlp.DecodeBytes(pk, x); err != nil {
            panic(err)
        }
        dkgComplaints = append(dkgComplaints, x)
    }
    return dkgComplaints
}

// AddDKGMasterPublicKey adds a DKGMasterPublicKey.
func (d *DexconGovernance) AddDKGMasterPublicKey(round uint64, masterPublicKey *coreTypes.DKGMasterPublicKey) {
    method := vm.GovernanceContractName2Method["addDKGMasterPublicKey"]

    encoded, err := rlp.EncodeToBytes(masterPublicKey)
    if err != nil {
        log.Error("failed to RLP encode mpk to bytes: %s", err)
        return
    }

    res, err := method.Inputs.Pack(big.NewInt(int64(round)), encoded)
    if err != nil {
        log.Error("failed to pack addDKGMasterPublicKey input: %s", err)
        return
    }

    data := append(method.Id(), res...)
    err = d.sendGovTx(context.Background(), data)
    if err != nil {
        log.Error("failed to send addDKGMasterPublicKey tx: %s", err)
    }
}

// DKGMasterPublicKeys gets all the DKGMasterPublicKey of round.
func (d *DexconGovernance) DKGMasterPublicKeys(round uint64) []*coreTypes.DKGMasterPublicKey {
    s := d.getGovState()
    var dkgMasterPKs []*coreTypes.DKGMasterPublicKey
    for _, pk := range s.DKGMasterPublicKeys(big.NewInt(int64(round))) {
        x := new(coreTypes.DKGMasterPublicKey)
        if err := rlp.DecodeBytes(pk, x); err != nil {
            panic(err)
        }
        dkgMasterPKs = append(dkgMasterPKs, x)
    }
    return dkgMasterPKs
}

// AddDKGFinalize adds a DKG finalize message.
func (d *DexconGovernance) AddDKGFinalize(round uint64, final *coreTypes.DKGFinalize) {
    method := vm.GovernanceContractName2Method["addDKGFinalize"]

    encoded, err := rlp.EncodeToBytes(final)
    if err != nil {
        log.Error("failed to RLP encode finalize to bytes: %s", err)
        return
    }

    res, err := method.Inputs.Pack(big.NewInt(int64(round)), encoded)
    if err != nil {
        log.Error("failed to pack addDKGFinalize input: %s", err)
        return
    }

    data := append(method.Id(), res...)
    err = d.sendGovTx(context.Background(), data)
    if err != nil {
        log.Error("failed to send addDKGFinalize tx: %s", err)
    }
}

// IsDKGFinal checks if DKG is final.
func (d *DexconGovernance) IsDKGFinal(round uint64) bool {
    s := d.getGovStateAtRound(round)
    threshold := 2*s.DKGSetSize().Uint64()/3 + 1
    count := s.DKGFinalizedsCount(big.NewInt(int64(round))).Uint64()
    return count >= threshold
}