feat(utxo-core): allow Buffer message type in signMessage/verifyMessage

Updates the BIP32 utility functions to accept both string and Buffer types as
message input, enhancing flexibility when working with different data formats.

Issue: BTC-0

Co-authored-by: llm-git <[email protected]>

Author: OttoAllmendinger

modules/utxo-core/src/bip32utils.ts

@@ -6,7 +6,7 @@ import { BIP32Interface } from '@bitgo/utxo-lib';
  * @see {bitcoinMessage.sign}
  */
 export function signMessage(
-  message: string,
+  message: string | Buffer,
   privateKey: BIP32Interface | Buffer,
   network: { messagePrefix: string }
 ): Buffer {
@@ -28,7 +28,7 @@ export function signMessage(
  * @see {bitcoinMessage.verify}
  */
 export function verifyMessage(
-  message: string,
+  message: string | Buffer,
   publicKey: BIP32Interface | Buffer,
   signature: Buffer,
   network: { messagePrefix: string }

modules/utxo-core/test/bip32utils.ts

@@ -11,16 +11,18 @@ describe('bip32utils', function () {
   }
   it('signMessage/verifyMessage', function () {
     const keys = getSeedBuffers(4).map((seed) => utxolib.bip32.fromSeed(seed));
-    const messages = ['hello', 'goodbye'];
+    const messages = ['hello', 'goodbye', Buffer.from('\x01\x02\x03'), Buffer.from('')];
     keys.forEach((key) => {
       messages.forEach((message) => {
         const signature = signMessage(message, key, utxolib.networks.bitcoin);
 
         keys.forEach((otherKey) => {
           messages.forEach((otherMessage) => {
+            const expectValid = message === otherMessage && key === otherKey;
+            assert.strictEqual(verifyMessage(otherMessage, otherKey, signature, utxolib.networks.bitcoin), expectValid);
             assert.strictEqual(
-              verifyMessage(otherMessage, otherKey, signature, utxolib.networks.bitcoin),
-              message === otherMessage && key === otherKey
+              verifyMessage(Buffer.from(otherMessage), otherKey, signature, utxolib.networks.bitcoin),
+              expectValid
             );
           });
         });