Keccak (umbracle#121)

* Add public keccak function

* Replace keccak in wallet with new one

keccak.go

@@ -0,0 +1,12 @@
+package web3
+
+import "golang.org/x/crypto/sha3"
+
+// Keccak256 calculates the Keccak256
+func Keccak256(v ...[]byte) []byte {
+	h := sha3.NewLegacyKeccak256()
+	for _, i := range v {
+		h.Write(i)
+	}
+	return h.Sum(nil)
+}

wallet/key.go

@@ -7,7 +7,6 @@ import (
 
 	"github.com/btcsuite/btcd/btcec"
 	"github.com/umbracle/go-web3"
-	"golang.org/x/crypto/sha3"
 )
 
 // S256 is the secp256k1 elliptic curve
@@ -31,7 +30,7 @@ func (k *Key) MarshallPrivateKey() ([]byte, error) {
 }
 
 func (k *Key) SignMsg(msg []byte) ([]byte, error) {
-	return k.Sign(keccak256(msg))
+	return k.Sign(web3.Keccak256(msg))
 }
 
 func (k *Key) Sign(hash []byte) ([]byte, error) {
@@ -56,7 +55,7 @@ func NewKey(priv *ecdsa.PrivateKey) *Key {
 }
 
 func pubKeyToAddress(pub *ecdsa.PublicKey) (addr web3.Address) {
-	b := keccak256(elliptic.Marshal(S256, pub.X, pub.Y)[1:])
+	b := web3.Keccak256(elliptic.Marshal(S256, pub.X, pub.Y)[1:])
 	copy(addr[:], b[12:])
 	return
 }
@@ -71,7 +70,7 @@ func GenerateKey() (*Key, error) {
 }
 
 func EcrecoverMsg(msg, signature []byte) (web3.Address, error) {
-	return Ecrecover(keccak256(msg), signature)
+	return Ecrecover(web3.Keccak256(msg), signature)
 }
 
 func Ecrecover(hash, signature []byte) (web3.Address, error) {
@@ -96,12 +95,3 @@ func RecoverPubkey(signature, hash []byte) (*ecdsa.PublicKey, error) {
 	}
 	return pub.ToECDSA(), nil
 }
-
-func keccak256(buf ...[]byte) []byte {
-	h := sha3.NewLegacyKeccak256()
-	for _, i := range buf {
-		h.Write(i)
-	}
-	b := h.Sum(nil)
-	return b
-}

wallet/signer.go

@@ -78,7 +78,7 @@ func signHash(tx *web3.Transaction, chainID uint64) []byte {
 		v.Set(a.NewUint(0))
 	}
 
-	hash := keccak256(v.MarshalTo(nil))
+	hash := web3.Keccak256(v.MarshalTo(nil))
 	fastrlp.DefaultArenaPool.Put(a)
 	return hash
 }

wallet/wallet_json.go

@@ -11,6 +11,7 @@ import (
 	"io/ioutil"
 	"strings"
 
+	"github.com/umbracle/go-web3"
 	"golang.org/x/crypto/pbkdf2"
 	"golang.org/x/crypto/scrypt"
 )
@@ -126,7 +127,7 @@ func (c *cryptoEncoding) getKDF(password []byte) ([]byte, error) {
 	}
 
 	// validate mac
-	mac := keccak256(key[16:32], c.CipherText)
+	mac := web3.Keccak256(key[16:32], c.CipherText)
 	if !bytes.Equal(mac, c.Mac) {
 		return nil, fmt.Errorf("incorrect mac")
 	}