Merge pull request #6692 from BitGo/BTC-2384.bip32Derivation

feat(utxo-core): add bip32derivation fields to BIP322 message signing

Author: davidkaplanbitgo

modules/utxo-core/src/bip322/toSign.ts

@@ -65,14 +65,20 @@ export function buildToSignPsbtForChainAndIndex(
   if (isTaprootChain(chain)) {
     throw new Error('BIP322 is not supported for Taproot script types.');
   }
-  const output = bitgo.outputScripts.createOutputScript2of3(
-    rootWalletKeys.deriveForChainAndIndex(chain, index).publicKeys,
-    bitgo.scriptTypeForChain(chain)
-  );
+  const walletKeys = rootWalletKeys.deriveForChainAndIndex(chain, index);
+  const output = bitgo.outputScripts.createOutputScript2of3(walletKeys.publicKeys, bitgo.scriptTypeForChain(chain));
 
-  return buildToSignPsbt(message, {
+  const psbt = buildToSignPsbt(message, {
     scriptPubKey: output.scriptPubKey,
     redeemScript: output.redeemScript,
     witnessScript: output.witnessScript,
   });
+
+  psbt.updateInput(
+    0,
+    bitgo.getPsbtBip32DerivationOutputUpdate(rootWalletKeys, walletKeys, bitgo.scriptTypeForChain(chain))
+  );
+  bitgo.addXpubsToPsbt(psbt, rootWalletKeys);
+
+  return psbt;
 }

modules/utxo-core/test/bip322/toSign.ts

@@ -53,25 +53,14 @@ describe('BIP322 toSign', function () {
         const toSpendTx = bip322.buildToSpendTransactionFromChainAndIndex(rootWalletKeys, chain, index, message);
         const toSignPsbt = bip322.buildToSignPsbtForChainAndIndex(message, rootWalletKeys, chain, index);
 
-        const derivedKeys = rootWalletKeys.deriveForChainAndIndex(chain, index);
-        const prv1 = derivedKeys.triple[0];
-        const prv2 = derivedKeys.triple[1];
-        assert.ok(prv1);
-        assert.ok(prv2);
-
         // Can sign the PSBT with the keys
-        toSignPsbt.signAllInputs(prv1, [utxolib.Transaction.SIGHASH_ALL]);
-        toSignPsbt.signAllInputs(prv2, [utxolib.Transaction.SIGHASH_ALL]);
+        // Should be able to use HD because we have the bip32Derivation information
+        toSignPsbt.signAllInputsHD(rootWalletKeys.triple[0]);
+        toSignPsbt.signAllInputsHD(rootWalletKeys.triple[1]);
 
         // Wrap the PSBT as a UtxoPsbt so that we can use the validateSignaturesOfInputCommon method
         const utxopsbt = utxolib.bitgo.createPsbtFromBuffer(toSignPsbt.toBuffer(), utxolib.networks.bitcoin);
-        derivedKeys.publicKeys.forEach((pubkey, i) => {
-          assert.deepStrictEqual(
-            utxopsbt.validateSignaturesOfInputCommon(0, pubkey),
-            i !== 2,
-            `Signature validation failed for public key at index ${i}`
-          );
-        });
+        utxopsbt.validateSignaturesOfAllInputs();
 
         // finalize and extract
         const tx = toSignPsbt.finalizeAllInputs().extractTransaction();
@@ -100,6 +89,7 @@ describe('BIP322 toSign', function () {
         assert.deepStrictEqual(toSpendTx.ins.length, 1, 'to_spend transaction must have one input');
         assert.deepStrictEqual(toSpendTx.outs.length, 1, 'to_spend transaction must have one output');
         assert.deepStrictEqual(toSpendTx.outs[0].value, BigInt(0), 'output value must be 0');
+        const derivedKeys = rootWalletKeys.deriveForChainAndIndex(chain, index);
         assert.deepStrictEqual(
           toSpendTx.outs[0].script.toString('hex'),
           utxolib.bitgo.outputScripts