1 files changed, 99 insertions, 0 deletions
diff --git a/crypto/eth/eth.go b/crypto/eth/eth.go
new file mode 100644
index 0000000..cb20d7d
--- /dev/null
+++ b/crypto/eth/eth.go
@@ -0,0 +1,99 @@
+// 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 eth
+
+import (
+	"crypto/ecdsa"
+
+	ethcrypto "github.com/ethereum/go-ethereum/crypto"
+
+	"github.com/dexon-foundation/dexon-consensus-core/common"
+	"github.com/dexon-foundation/dexon-consensus-core/crypto"
+)
+
+// PrivateKey represents a private key structure used in geth and implments
+// Crypto.PrivateKey interface.
+type PrivateKey struct {
+	privateKey ecdsa.PrivateKey
+	publicKey  PublicKey
+}
+
+// PublicKey represents a public key structure used in geth and implements
+// Crypto.PublicKey interface.
+type PublicKey struct {
+	publicKey []byte
+}
+
+// NewPrivateKey creates a new PrivateKey structure.
+func NewPrivateKey() (*PrivateKey, error) {
+	key, err := ethcrypto.GenerateKey()
+	if err != nil {
+		return nil, err
+	}
+	return &PrivateKey{
+		privateKey: *key,
+		publicKey:  *newPublicKey(key),
+	}, nil
+}
+
+// newPublicKey creates a new PublicKey structure.
+func newPublicKey(prvKey *ecdsa.PrivateKey) *PublicKey {
+	return &PublicKey{
+		publicKey: ethcrypto.CompressPubkey(&prvKey.PublicKey),
+	}
+}
+
+// DecompressPubkey parses a public key in the 33-byte compressed format.
+func DecompressPubkey(pubkey []byte) (PublicKey, error) {
+	_, err := ethcrypto.DecompressPubkey(pubkey)
+	return PublicKey{
+		publicKey: pubkey,
+	}, err
+}
+
+// PublicKey returns the public key associate this private key.
+func (prv *PrivateKey) PublicKey() crypto.PublicKey {
+	return prv.publicKey
+}
+
+// Sign calculates an ECDSA signature.
+//
+// This function is susceptible to chosen plaintext attacks that can leak
+// information about the private key that is used for signing. Callers must
+// be aware that the given hash cannot be chosen by an adversery. Common
+// solution is to hash any input before calculating the signature.
+//
+// The produced signature is in the [R || S || V] format where V is 0 or 1.
+func (prv *PrivateKey) Sign(hash common.Hash) (sig crypto.Signature, err error) {
+	s, err := ethcrypto.Sign(hash[:], &prv.privateKey)
+	// Magic!
+	sig = crypto.Signature(s[:64])
+	return
+}
+
+// VerifySignature checks that the given public key created signature over hash.
+// The public key should be in compressed (33 bytes) or uncompressed (65 bytes) format.
+// The signature should have the 64 byte [R || S] format.
+func (pub PublicKey) VerifySignature(hash common.Hash, signature crypto.Signature) bool {
+	return ethcrypto.VerifySignature(pub.publicKey, hash[:], signature)
+}
+
+// Compress encodes a public key to the 33-byte compressed format.
+func (pub PublicKey) Compress() []byte {
+	return pub.publicKey
+}