// Copyright 2018 The dexon-consensus-core Authors
// This file is part of the dexon-consensus-core library.
//
// The dexon-consensus-core library is free software: you can redistribute it
// and/or modify it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation, either version 3 of the License,
// or (at your option) any later version.
//
// The dexon-consensus-core library is distributed in the hope that it will be
// useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
// General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the dexon-consensus-core library. If not, see
// <http://www.gnu.org/licenses/>.
package core
import (
"encoding/binary"
"github.com/dexon-foundation/dexon-consensus-core/common"
"github.com/dexon-foundation/dexon-consensus-core/core/types"
"github.com/dexon-foundation/dexon-consensus-core/crypto"
)
func hashWitness(block *types.Block) (common.Hash, error) {
binaryTime, err := block.Witness.Timestamp.MarshalBinary()
if err != nil {
return common.Hash{}, err
}
binaryHeight := make([]byte, 8)
binary.LittleEndian.PutUint64(binaryHeight, block.Witness.Height)
hash := crypto.Keccak256Hash(
block.Witness.ParentHash[:],
binaryTime,
binaryHeight)
return hash, nil
}
func verifyWitnessSignature(pubkey crypto.PublicKey,
witnessBlock *types.Block, sig crypto.Signature) (bool, error) {
hash, err := hashWitness(witnessBlock)
if err != nil {
return false, err
}
return pubkey.VerifySignature(hash, sig), nil
}
func hashBlock(block *types.Block) (common.Hash, error) {
hashPosition := hashPosition(block.Position)
// Handling Block.Acks.
binaryAcks := make([][]byte, len(block.Acks))
for idx, ack := range block.Acks {
binaryAcks[idx] = ack[:]
}
hashAcks := crypto.Keccak256Hash(binaryAcks...)
binaryTimestamp, err := block.Timestamp.MarshalBinary()
if err != nil {
return common.Hash{}, err
}
payloadHash := crypto.Keccak256Hash(block.Payload)
hash := crypto.Keccak256Hash(
block.ProposerID.Hash[:],
block.ParentHash[:],
hashPosition[:],
hashAcks[:],
binaryTimestamp[:],
payloadHash[:])
return hash, nil
}
func verifyBlockSignature(pubkey crypto.PublicKey,
block *types.Block, sig crypto.Signature) (bool, error) {
hash, err := hashBlock(block)
if err != nil {
return false, err
}
return pubkey.VerifySignature(hash, sig), nil
}
func hashVote(vote *types.Vote) common.Hash {
binaryPeriod := make([]byte, 8)
binary.LittleEndian.PutUint64(binaryPeriod, vote.Period)
hashPosition := hashPosition(vote.Position)
hash := crypto.Keccak256Hash(
vote.ProposerID.Hash[:],
vote.BlockHash[:],
binaryPeriod,
hashPosition[:],
[]byte{byte(vote.Type)},
)
return hash
}
func verifyVoteSignature(vote *types.Vote, sigToPub SigToPubFn) (bool, error) {
hash := hashVote(vote)
pubKey, err := sigToPub(hash, vote.Signature)
if err != nil {
return false, err
}
if vote.ProposerID != types.NewNodeID(pubKey) {
return false, nil
}
return true, nil
}
func hashCRS(block *types.Block, crs common.Hash) common.Hash {
hashPos := hashPosition(block.Position)
return crypto.Keccak256Hash(crs[:], hashPos[:])
}
func verifyCRSSignature(block *types.Block, crs common.Hash, sigToPub SigToPubFn) (
bool, error) {
hash := hashCRS(block, crs)
pubKey, err := sigToPub(hash, block.CRSSignature)
if err != nil {
return false, err
}
if block.ProposerID != types.NewNodeID(pubKey) {
return false, nil
}
return true, nil
}
func hashPosition(position types.Position) common.Hash {
binaryShardID := make([]byte, 4)
binary.LittleEndian.PutUint32(binaryShardID, position.ShardID)
binaryChainID := make([]byte, 4)
binary.LittleEndian.PutUint32(binaryChainID, position.ChainID)
binaryHeight := make([]byte, 8)
binary.LittleEndian.PutUint64(binaryHeight, position.Height)
return crypto.Keccak256Hash(
binaryShardID,
binaryChainID,
binaryHeight,
)
}
func hashDKGPrivateShare(prvShare *types.DKGPrivateShare) common.Hash {
binaryRound := make([]byte, 8)
binary.LittleEndian.PutUint64(binaryRound, prvShare.Round)
return crypto.Keccak256Hash(
prvShare.ProposerID.Hash[:],
binaryRound,
prvShare.PrivateShare.Bytes(),
)
}
func verifyDKGPrivateShareSignature(
prvShare *types.DKGPrivateShare, sigToPub SigToPubFn) (bool, error) {
hash := hashDKGPrivateShare(prvShare)
pubKey, err := sigToPub(hash, prvShare.Signature)
if err != nil {
return false, err
}
if prvShare.ProposerID != types.NewNodeID(pubKey) {
return false, nil
}
return true, nil
}
func hashDKGMasterPublicKey(mpk *types.DKGMasterPublicKey) common.Hash {
binaryRound := make([]byte, 8)
binary.LittleEndian.PutUint64(binaryRound, mpk.Round)
return crypto.Keccak256Hash(
mpk.ProposerID.Hash[:],
mpk.DKGID.GetLittleEndian(),
mpk.PublicKeyShares.MasterKeyBytes(),
binaryRound,
)
}
func verifyDKGMasterPublicKeySignature(
mpk *types.DKGMasterPublicKey, sigToPub SigToPubFn) (bool, error) {
hash := hashDKGMasterPublicKey(mpk)
pubKey, err := sigToPub(hash, mpk.Signature)
if err != nil {
return false, err
}
if mpk.ProposerID != types.NewNodeID(pubKey) {
return false, nil
}
return true, nil
}
func hashDKGComplaint(complaint *types.DKGComplaint) common.Hash {
binaryRound := make([]byte, 8)
binary.LittleEndian.PutUint64(binaryRound, complaint.Round)
hashPrvShare := hashDKGPrivateShare(&complaint.PrivateShare)
return crypto.Keccak256Hash(
complaint.ProposerID.Hash[:],
binaryRound,
hashPrvShare[:],
)
}
func verifyDKGComplaintSignature(
complaint *types.DKGComplaint, sigToPub SigToPubFn) (bool, error) {
hash := hashDKGComplaint(complaint)
pubKey, err := sigToPub(hash, complaint.Signature)
if err != nil {
return false, err
}
if complaint.ProposerID != types.NewNodeID(pubKey) {
return false, nil
}
return true, nil
}
func hashDKGPartialSignature(psig *types.DKGPartialSignature) common.Hash {
binaryRound := make([]byte, 8)
binary.LittleEndian.PutUint64(binaryRound, psig.Round)
return crypto.Keccak256Hash(
psig.ProposerID.Hash[:],
binaryRound,
psig.PartialSignature[:],
)
}
func verifyDKGPartialSignatureSignature(
psig *types.DKGPartialSignature, sigToPub SigToPubFn) (bool, error) {
hash := hashDKGPartialSignature(psig)
pubKey, err := sigToPub(hash, psig.Signature)
if err != nil {
return false, err
}
if psig.ProposerID != types.NewNodeID(pubKey) {
return false, nil
}
return true, nil
}
