// 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 (
"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"
)
type keyHolder struct {
prvKey crypto.PrivateKey
pubKey crypto.PublicKey
sigToPub SigToPubFn
}
func newKeyHolder(prvKey crypto.PrivateKey, sigToPub SigToPubFn) *keyHolder {
return &keyHolder{
prvKey: prvKey,
pubKey: prvKey.PublicKey(),
sigToPub: sigToPub,
}
}
// SignBlock implements core.Signer.
func (h *keyHolder) SignBlock(b *types.Block) (err error) {
b.ProposerID = types.NewNodeID(h.pubKey)
if b.Hash, err = hashBlock(b); err != nil {
return
}
if b.Signature, err = h.prvKey.Sign(b.Hash); err != nil {
return
}
return
}
// SignVote implements core.Signer.
func (h *keyHolder) SignVote(v *types.Vote) (err error) {
v.ProposerID = types.NewNodeID(h.pubKey)
v.Signature, err = h.prvKey.Sign(hashVote(v))
return
}
// SignCRS implements core.Signer
func (h *keyHolder) SignCRS(b *types.Block, crs common.Hash) (err error) {
if b.ProposerID != types.NewNodeID(h.pubKey) {
err = ErrInvalidProposerID
return
}
b.CRSSignature, err = h.prvKey.Sign(hashCRS(b, crs))
return
}
// VerifyBlock implements core.CryptoVerifier.
func (h *keyHolder) VerifyBlock(b *types.Block) (err error) {
hash, err := hashBlock(b)
if err != nil {
return
}
if hash != b.Hash {
err = ErrIncorrectHash
return
}
pubKey, err := h.sigToPub(b.Hash, b.Signature)
if err != nil {
return
}
if !b.ProposerID.Equal(crypto.Keccak256Hash(pubKey.Bytes())) {
err = ErrIncorrectSignature
return
}
return
}
// VerifyVote implements core.CryptoVerifier.
func (h *keyHolder) VerifyVote(v *types.Vote) (bool, error) {
return verifyVoteSignature(v, h.sigToPub)
}
// VerifyWitness implements core.CryptoVerifier.
func (h *keyHolder) VerifyCRS(b *types.Block, crs common.Hash) (bool, error) {
return verifyCRSSignature(b, crs, h.sigToPub)
}