1 files changed, 58 insertions, 0 deletions
diff --git a/cli/verify_signature.go b/cli/verify_signature.go
new file mode 100644
index 0000000..631adac
--- /dev/null
+++ b/cli/verify_signature.go
@@ -0,0 +1,58 @@
+package main
+
+import (
+    "bytes"
+    "crypto/ecdsa"
+    "fmt"
+    "log"
+
+    "github.com/ethereum/go-ethereum/common/hexutil"
+    "github.com/ethereum/go-ethereum/crypto"
+)
+
+func main() {
+    privateKey, err := crypto.HexToECDSA("fad9c8855b740a0b7ed4c221dbad0f33a83a49cad6b3fe8d5817ac83d38b6a19")
+    if err != nil {
+        log.Fatal(err)
+    }
+
+    publicKey := privateKey.Public()
+    publicKeyECDSA, ok := publicKey.(*ecdsa.PublicKey)
+    if !ok {
+        log.Fatal("error casting public key to ECDSA")
+    }
+
+    publicKeyBytes := crypto.FromECDSAPub(publicKeyECDSA)
+
+    data := []byte("decartography")
+    hash := crypto.Keccak256Hash(data)
+    fmt.Println(hash.Hex()) // 0xfe2b8f0bae0d344e95a421b9cc1a32ef07083cc85d007146259221fece9264a7
+
+    signature, err := crypto.Sign(hash.Bytes(), privateKey)
+    if err != nil {
+        log.Fatal(err)
+    }
+
+    fmt.Println(hexutil.Encode(signature))
+
+    sigPublicKey, err := crypto.Ecrecover(hash.Bytes(), signature)
+    if err != nil {
+        log.Fatal(err)
+    }
+
+    matches := bytes.Equal(sigPublicKey, publicKeyBytes)
+    fmt.Println(matches) // true
+
+    sigPublicKeyECDSA, err := crypto.SigToPub(hash.Bytes(), signature)
+    if err != nil {
+        log.Fatal(err)
+    }
+
+    sigPublicKeyBytes := crypto.FromECDSAPub(sigPublicKeyECDSA)
+    matches = bytes.Equal(sigPublicKeyBytes, publicKeyBytes)
+    fmt.Println(matches) // true
+
+    signatureNoRecoverID := signature[:len(signature)-1] // remove recovery id
+    verified := crypto.VerifySignature(publicKeyBytes, hash.Bytes(), signatureNoRecoverID)
+    fmt.Println(verified) // true
+}
+\ No newline at end of file