feat: ✨ eth: RecoverSignerAddress

Signed-off-by: thanhpp <[email protected]>

pkg/eth/recover.go

@@ -0,0 +1,44 @@
+package eth
+
+import (
+	"fmt"
+
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+	"github.com/ethereum/go-ethereum/crypto"
+)
+
+const signatureLength = 65
+
+func RecoverSignerAddress(hexEncodedHash string, hexEncodedSignature string) (common.Address, error) {
+	hash, err := hexutil.Decode(hexEncodedHash)
+	if err != nil {
+		return common.Address{}, fmt.Errorf("decode hash error: %w", err)
+	}
+
+	signature, err := hexutil.Decode(hexEncodedSignature)
+	if err != nil {
+		return common.Address{}, fmt.Errorf("decode signature error: %w", err)
+	}
+
+	// Signature in Ethereum consists of R, S, V; the V is at last byte, R and S are the rest.
+	// The standard Ethereum signature is 65 bytes (R: 32 bytes, S: 32 bytes, V: 1 byte).
+	// Ensure the signature is 65 bytes and split it into R, S, and V components.
+	if len(signature) != signatureLength {
+		return common.Address{}, fmt.Errorf("invalid signature length, expect: %d, got: %v", signatureLength, len(signature))
+	}
+
+	// Ethereum uses a 'recovery id' for V, but go-ethereum expects V to be 27 or 28.
+	signature[64] += 27
+
+	// Recover the public key from the signature
+	pubKey, err := crypto.SigToPub(hash, signature)
+	if err != nil {
+		return common.Address{}, fmt.Errorf("signature to public key error: %w", err)
+	}
+
+	// Derive the Ethereum address from the public key
+	address := crypto.PubkeyToAddress(*pubKey)
+
+	return address, nil
+}