add capability for only pubkeys to be supplied to whielpool client, with an external signing interface

src/main/java/com/samourai/wallet/bip47/rpc/java/Bip47UtilJava.java

@@ -3,6 +3,8 @@ package com.samourai.wallet.bip47.rpc.java;
 import com.samourai.wallet.bip47.BIP47UtilGeneric;
 import com.samourai.wallet.bip47.rpc.secretPoint.ISecretPoint;
 import com.samourai.wallet.bip47.rpc.secretPoint.ISecretPointFactory;
+import com.samourai.wallet.hd.HD_Address;
+
 import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
 import java.security.NoSuchProviderException;
@@ -27,6 +29,11 @@ public class Bip47UtilJava extends BIP47UtilGeneric {
                 InvalidKeyException {
           return new SecretPointJava(dataPrv, dataPub);
         }
+
+        @Override
+        public ISecretPoint newSecretPoint(HD_Address address, byte[] dataPub) throws NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException, InvalidKeyException {
+          return new SecretPointJava(address.getECKey().getPrivKeyBytes(), dataPub);
+        }
       };
 
   private Bip47UtilJava() {

src/main/java/com/samourai/wallet/bip47/rpc/java/SecretPointFactoryJava.java

@@ -2,6 +2,8 @@ package com.samourai.wallet.bip47.rpc.java;
 
 import com.samourai.wallet.bip47.rpc.secretPoint.ISecretPoint;
 import com.samourai.wallet.bip47.rpc.secretPoint.ISecretPointFactory;
+import com.samourai.wallet.hd.HD_Address;
+
 import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
 import java.security.NoSuchProviderException;
@@ -17,11 +19,14 @@ public class SecretPointFactoryJava implements ISecretPointFactory {
         return instance;
     }
 
-    private SecretPointFactoryJava() {}
+    public SecretPointFactoryJava() {}
 
     @Override
     public ISecretPoint newSecretPoint(byte[] dataPrv, byte[] dataPub) throws NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException, InvalidKeyException {
         return new SecretPointJava(dataPrv, dataPub);
     }
 
+    public ISecretPoint newSecretPoint(HD_Address address, byte[] dataPub) throws NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException, InvalidKeyException {
+        return new SecretPointJava(address.getECKey().getPrivKeyBytes(), dataPub);
+    }
 }

src/main/java/com/samourai/wallet/bip47/rpc/secretPoint/ISecretPointFactory.java

@@ -1,5 +1,7 @@
 package com.samourai.wallet.bip47.rpc.secretPoint;
 
+import com.samourai.wallet.hd.HD_Address;
+
 import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
 import java.security.NoSuchProviderException;
@@ -8,5 +10,5 @@ import java.security.spec.InvalidKeySpecException;
 public interface ISecretPointFactory {
 
     ISecretPoint newSecretPoint(byte[] dataPrv, byte[] dataPub) throws NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException, InvalidKeyException;
-
+    ISecretPoint newSecretPoint(HD_Address address, byte[] dataPub) throws NoSuchAlgorithmException, NoSuchProviderException, InvalidKeySpecException, InvalidKeyException;
 }

src/main/java/com/samourai/wallet/client/BipWallet.java

@@ -22,7 +22,7 @@ public class BipWallet {
       IIndexHandler indexChangeHandler,
       AddressType addressType) {
     this.account = account;
-    this.bipWallet = new HD_Wallet(addressType.getPurpose(), bip44w);
+    this.bipWallet = bip44w.getSeed() == null ? new HD_Wallet(bip44w.getParams(), bip44w.getAccounts()) : new HD_Wallet(addressType.getPurpose(), bip44w);
     this.indexHandler = indexHandler;
     this.indexChangeHandler = indexChangeHandler;
   }

src/main/java/com/samourai/wallet/hd/HD_Address.java

@@ -120,4 +120,8 @@ public class HD_Address {
     public static String getPathFull(int purpose, int coinType, int account, int chain, int address) {
         return "m/"+purpose+"'/"+coinType+"'/"+account+"'/"+chain+"/"+address;
     }
+
+    public NetworkParameters getParams() {
+        return mParams;
+    }
 }

src/main/java/com/samourai/wallet/hd/HD_Wallet.java

@@ -10,10 +10,7 @@ import org.bitcoinj.crypto.*;
 
 import java.nio.ByteBuffer;
 import java.nio.ByteOrder;
-import java.util.Arrays;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 
 public class HD_Wallet {
     private byte[] mSeed = null;
@@ -75,6 +72,21 @@ public class HD_Wallet {
         }
     }
 
+    public HD_Wallet(NetworkParameters params, Map<Integer, HD_Account> xpub) throws AddressFormatException {
+        mParams = params;
+
+        // initialize mAccounts and xpubs
+        mAccounts = new LinkedHashMap<>();
+        xpubs = new String[xpub.size()];
+        List<Integer> indexList = new ArrayList<>(xpub.keySet());
+        for(int i = 0; i < indexList.size(); i++) {
+            Integer accountIndex = indexList.get(i);
+            HD_Account account = new HD_Account(mParams, xpub.get(accountIndex).strXPUB, accountIndex);
+            mAccounts.put(accountIndex, account);
+            xpubs[i] = account.xpubstr();
+        }
+    }
+
     private static DeterministicKey computeRootKey(int purpose, List<String> mWordList, String strPassphrase, NetworkParameters params) {
         byte[] hd_seed = MnemonicCode.toSeed(mWordList, strPassphrase);
         DeterministicKey mKey = HDKeyDerivation.createMasterPrivateKey(hd_seed);
@@ -104,6 +116,10 @@ public class HD_Wallet {
         return mParams;
     }
 
+    public Map<Integer, HD_Account> getAccounts() {
+        return mAccounts;
+    }
+
     public HD_Account getAccount(int accountIdx) {
         HD_Account hdAccount = mAccounts.get(accountIdx);
         if (hdAccount == null) {

src/main/java/com/samourai/wallet/send/provider/AbstractUtxoKeyProvider.java

@@ -0,0 +1,10 @@
+package com.samourai.wallet.send.provider;
+
+import org.bitcoinj.core.ECKey;
+
+public abstract class AbstractUtxoKeyProvider implements UtxoKeyProvider {
+    @Override
+    public ECKey _getPrivKey(String utxoHash, int utxoIndex) throws Exception {
+        return getAddress(utxoHash, utxoIndex).getECKey();
+    }
+}

src/main/java/com/samourai/wallet/send/provider/SimpleUtxoKeyProvider.java

@@ -1,5 +1,6 @@
 package com.samourai.wallet.send.provider;
 
+import com.samourai.wallet.hd.HD_Address;
 import org.bitcoinj.core.ECKey;
 import org.bitcoinj.core.TransactionOutPoint;
 
@@ -17,4 +18,9 @@ public class SimpleUtxoKeyProvider implements UtxoKeyProvider {
   public ECKey _getPrivKey(String utxoHash, int utxoIndex) throws Exception {
     return keys.get(utxoHash + ":" + utxoIndex);
   }
+
+    @Override
+    public HD_Address getAddress(String utxoHash, int utxoIndex) throws Exception {
+        return null;
+    }
 }

src/main/java/com/samourai/wallet/send/provider/UtxoKeyProvider.java

@@ -1,8 +1,10 @@
 package com.samourai.wallet.send.provider;
 
+import com.samourai.wallet.hd.HD_Address;
 import org.bitcoinj.core.ECKey;
 
 public interface UtxoKeyProvider {
 
     ECKey _getPrivKey(String utxoHash, int utxoIndex) throws Exception;
+    HD_Address getAddress(String utxoHash, int utxoIndex) throws Exception;
 }

src/main/java/com/samourai/whirlpool/client/mix/handler/DefaultSigningHandler.java

@@ -0,0 +1,48 @@
+package com.samourai.whirlpool.client.mix.handler;
+
+import com.samourai.wallet.hd.HD_Address;
+import com.samourai.wallet.segwit.SegwitAddress;
+import com.samourai.wallet.send.SendFactoryGeneric;
+import com.samourai.wallet.send.exceptions.SignTxException;
+import com.samourai.wallet.send.provider.UtxoKeyProvider;
+import org.bitcoinj.core.Coin;
+import org.bitcoinj.core.Transaction;
+import org.bitcoinj.crypto.TransactionSignature;
+import org.bitcoinj.script.Script;
+
+public class DefaultSigningHandler implements SigningHandler {
+    @Override
+    public String signMessage(HD_Address hdAddress, String message) {
+        return hdAddress.getECKey().signMessage(message);
+    }
+
+    @Override
+    public Transaction signTx0Transaction(Transaction transaction, UtxoKeyProvider utxoKeyProvider) throws SignTxException {
+        byte[] signedTx = signTx0Transaction(transaction.bitcoinSerialize(), utxoKeyProvider);
+        if(signedTx != null) {
+            return new Transaction(transaction.getParams(), signedTx);
+        }
+
+        SendFactoryGeneric.getInstance().signTransaction(transaction, getUtxoKeyProvider(utxoKeyProvider));
+        return transaction;
+    }
+
+    protected byte[] signTx0Transaction(byte[] transactionBytes, UtxoKeyProvider utxoKeyProvider) throws SignTxException {
+        return null;
+    }
+
+    protected UtxoKeyProvider getUtxoKeyProvider(UtxoKeyProvider utxoKeyProvider) {
+        return utxoKeyProvider;
+    }
+
+    @Override
+    public byte[] signMixTransaction(byte[] transaction, int inputIndex, HD_Address hdAddress, long spendAmount) {
+        final SegwitAddress segwitAddress = new SegwitAddress(hdAddress.getECKey(), hdAddress.getParams());
+        final Script redeemScript = segwitAddress.segWitRedeemScript();
+        final Script scriptCode = redeemScript.scriptCode();
+
+        Transaction tx = new Transaction(hdAddress.getParams(), transaction);
+        TransactionSignature sig = tx.calculateWitnessSignature(inputIndex, hdAddress.getECKey(), scriptCode, Coin.valueOf(spendAmount), Transaction.SigHash.ALL, false);
+        return sig.encodeToBitcoin();
+    }
+}

src/main/java/com/samourai/whirlpool/client/mix/handler/PremixHandler.java

@@ -1,20 +1,21 @@
 package com.samourai.whirlpool.client.mix.handler;
 
-import com.samourai.wallet.segwit.SegwitAddress;
+import com.samourai.wallet.hd.HD_Address;
 import com.samourai.whirlpool.client.utils.ClientUtils;
 import org.bitcoinj.core.*;
 import org.bitcoinj.crypto.TransactionSignature;
-import org.bitcoinj.script.Script;
 
 public class PremixHandler implements IPremixHandler {
   private UtxoWithBalance utxo;
-  private ECKey utxoKey;
+  private HD_Address utxoAddress;
   private String userPreHash;
+  private SigningHandler signingHandler;
 
-  public PremixHandler(UtxoWithBalance utxo, ECKey utxoKey, String userPreHash) {
+  public PremixHandler(UtxoWithBalance utxo, HD_Address utxoAddress, String userPreHash, SigningHandler signingHandler) {
     this.utxo = utxo;
-    this.utxoKey = utxoKey;
+    this.utxoAddress = utxoAddress;
     this.userPreHash = userPreHash;
+    this.signingHandler = signingHandler;
   }
 
   @Override
@@ -27,19 +28,14 @@ public class PremixHandler implements IPremixHandler {
       throws Exception {
     // TODO SendFactoryGeneric.getInstance().signInput(utxoKey, params, tx, inputIndex);
     long spendAmount = utxo.getBalance();
-    signInputSegwit(tx, inputIndex, utxoKey, spendAmount, params);
+    signInputSegwit(tx, inputIndex, utxoAddress.getECKey(), spendAmount, params);
   }
 
   // TODO
   protected void signInputSegwit(
           Transaction tx, int inputIdx, ECKey ecKey, long spendAmount, NetworkParameters params) {
-    final SegwitAddress segwitAddress = new SegwitAddress(ecKey, params);
-    final Script redeemScript = segwitAddress.segWitRedeemScript();
-    final Script scriptCode = redeemScript.scriptCode();
-
-    TransactionSignature sig =
-        tx.calculateWitnessSignature(
-            inputIdx, ecKey, scriptCode, Coin.valueOf(spendAmount), Transaction.SigHash.ALL, false);
+    byte[] sigBytes = signingHandler.signMixTransaction(tx.bitcoinSerialize(), inputIdx, utxoAddress, spendAmount);
+    TransactionSignature sig = TransactionSignature.decodeFromBitcoin(sigBytes, false, false);
     final TransactionWitness witness = new TransactionWitness(2);
     witness.setPush(0, sig.encodeToBitcoin());
     witness.setPush(1, ecKey.getPubKey());
@@ -48,7 +44,7 @@ public class PremixHandler implements IPremixHandler {
 
   @Override
   public String signMessage(String message) {
-    return utxoKey.signMessage(message);
+    return signingHandler.signMessage(utxoAddress, message);
   }
 
   @Override

src/main/java/com/samourai/whirlpool/client/mix/handler/SigningHandler.java

@@ -0,0 +1,12 @@
+package com.samourai.whirlpool.client.mix.handler;
+
+import com.samourai.wallet.hd.HD_Address;
+import com.samourai.wallet.send.exceptions.SignTxException;
+import com.samourai.wallet.send.provider.UtxoKeyProvider;
+import org.bitcoinj.core.Transaction;
+
+public interface SigningHandler {
+    String signMessage(HD_Address hdAddress, String message);
+    Transaction signTx0Transaction(Transaction transaction, UtxoKeyProvider utxoKeyProvider) throws SignTxException;
+    byte[] signMixTransaction(byte[] transaction, int inputIndex, HD_Address hdAddress, long spendAmount);
+}

src/main/java/com/samourai/whirlpool/client/tx0/Tx0Service.java

@@ -36,14 +36,12 @@ public class Tx0Service {
 
   private final Bech32UtilGeneric bech32Util = Bech32UtilGeneric.getInstance();
   private final FormatsUtilGeneric formatsUtilGeneric = FormatsUtilGeneric.getInstance();
-  private final XorMask xorMask;
   private final FeeUtil feeUtil = FeeUtil.getInstance();
 
   private WhirlpoolWalletConfig config;
 
   public Tx0Service(WhirlpoolWalletConfig config) {
     this.config = config;
-    xorMask = XorMask.getInstance(config.getSecretPointFactory());
   }
 
   private int computeNbPremixMax(
@@ -275,12 +273,19 @@ public class Tx0Service {
     ECKey firstInputKey = utxoKeyProvider._getPrivKey(firstInput.tx_hash, firstInput.tx_output_n);
     String feePaymentCode = tx0Data.getFeePaymentCode();
     byte[] feePayload = tx0Data.getFeePayload();
-    byte[] feePayloadMasked =
+    XorMask xorMask = XorMask.getInstance(config.getSecretPointFactory());
+    byte[] feePayloadMasked = firstInputKey.hasPrivKey() ?
         xorMask.mask(
             feePayload,
             feePaymentCode,
             params,
             firstInputKey.getPrivKeyBytes(),
+            firstInput.computeOutpoint(params)) :
+        xorMask.mask(
+            feePayload,
+            feePaymentCode,
+            params,
+            utxoKeyProvider.getAddress(firstInput.tx_hash, firstInput.tx_output_n),
             firstInput.computeOutpoint(params));
     if (log.isDebugEnabled()) {
       log.debug("feePayloadHex=" + Hex.toHexString(feePayload));
@@ -533,15 +538,15 @@ public class Tx0Service {
       }
     }
 
-    signTx0(tx, utxoKeyProvider);
+    tx = signTx0(tx, utxoKeyProvider);
     tx.verify();
 
     Tx0 tx0 = new Tx0(tx0Preview, tx, premixOutputs, changeOutputs);
     return tx0;
   }
 
-  protected void signTx0(Transaction tx, UtxoKeyProvider utxoKeyProvider) throws Exception {
-    SendFactoryGeneric.getInstance().signTransaction(tx, utxoKeyProvider);
+  protected Transaction signTx0(Transaction tx, UtxoKeyProvider utxoKeyProvider) throws Exception {
+      return config.getSigningHandler().signTx0Transaction(tx, utxoKeyProvider);
   }
 
   protected Collection<Tx0Data> fetchTx0Data(String partnerId) throws Exception {

src/main/java/com/samourai/whirlpool/client/wallet/PostmixIndexService.java

@@ -51,7 +51,7 @@ public class PostmixIndexService {
     }
     HD_Address hdAddress = walletPostmix.getAddressAt(Chain.RECEIVE.getIndex(), postmixIndex);
     String outputAddress = bech32Util.toBech32(hdAddress, config.getNetworkParameters());
-    String signature = hdAddress.getECKey().signMessage(outputAddress);
+    String signature = config.getSigningHandler().signMessage(hdAddress, outputAddress);
     CheckOutputRequest checkOutputRequest = new CheckOutputRequest(outputAddress, signature);
     return config.getServerApi().checkOutput(checkOutputRequest);
   }

src/main/java/com/samourai/whirlpool/client/wallet/WhirlpoolWalletConfig.java

@@ -7,6 +7,8 @@ import com.samourai.wallet.bip47.rpc.java.SecretPointFactoryJava;
 import com.samourai.wallet.bip47.rpc.secretPoint.ISecretPointFactory;
 import com.samourai.wallet.util.FormatsUtilGeneric;
 import com.samourai.whirlpool.client.exception.NotifiableException;
+import com.samourai.whirlpool.client.mix.handler.DefaultSigningHandler;
+import com.samourai.whirlpool.client.mix.handler.SigningHandler;
 import com.samourai.whirlpool.client.tx0.ITx0ParamServiceConfig;
 import com.samourai.whirlpool.client.utils.ClientUtils;
 import com.samourai.whirlpool.client.wallet.beans.IndexRange;
@@ -31,6 +33,7 @@ public class WhirlpoolWalletConfig extends WhirlpoolClientConfig implements ITx0
 
   private DataSourceFactory dataSourceFactory;
   private DataPersisterFactory dataPersisterFactory;
+  private SigningHandler signingHandler = new DefaultSigningHandler();
   private boolean mobile;
 
   private int maxClients;
@@ -371,6 +374,14 @@ public class WhirlpoolWalletConfig extends WhirlpoolClientConfig implements ITx0
     this.secretPointFactory = secretPointFactory;
   }
 
+  public SigningHandler getSigningHandler() {
+        return signingHandler;
+    }
+
+  public void setSigningHandler(SigningHandler signingHandler) {
+        this.signingHandler = signingHandler;
+    }
+
   public Map<String, String> getConfigInfo() {
     Map<String, String> configInfo = new LinkedHashMap<String, String>();
     configInfo.put("dataSourceFactory", dataSourceFactory.getClass().getSimpleName());

src/main/java/com/samourai/whirlpool/client/wallet/data/utxo/BasicUtxoSupplier.java

@@ -185,6 +185,16 @@ public abstract class BasicUtxoSupplier extends BasicSupplier<UtxoData>
     return premixAddress.getECKey();
   }
 
+  @Override
+  public HD_Address getAddress(String utxoHash, int utxoIndex) throws Exception {
+    WhirlpoolUtxo whirlpoolUtxo = findUtxo(utxoHash, utxoIndex);
+    if (whirlpoolUtxo == null) {
+       throw new Exception("Utxo not found: " + utxoHash + ":" + utxoIndex);
+    }
+
+    return getAddress(whirlpoolUtxo);
+  }
+
   protected byte[] _getPrivKeyBytes(WhirlpoolUtxo whirlpoolUtxo) {
       return null;
   }

src/main/java/com/samourai/whirlpool/client/wallet/orchestrator/MixOrchestratorImpl.java

@@ -204,7 +204,7 @@ public class MixOrchestratorImpl extends MixOrchestrator {
     String premix00Bech32 = Bech32UtilGeneric.getInstance().toBech32(premix00, params);
     String userPreHash = ClientUtils.sha256Hash(premix00Bech32);
 
-    return new PremixHandler(utxoWithBalance, premixKey, userPreHash);
+    return new PremixHandler(utxoWithBalance, premixAddress, userPreHash, whirlpoolWallet.getConfig().getSigningHandler());
   }
 
   private IPostmixHandler computePostmixHandler(WhirlpoolUtxo whirlpoolUtxo) {

src/main/java/com/samourai/whirlpool/protocol/util/XorMask.java

@@ -45,6 +45,24 @@ public class XorMask {
     return dataMasked;
   }
 
+  public byte[] mask(
+      byte[] dataToMask,
+      String paymentCodeOfSecretAccount,
+      NetworkParameters params,
+      HD_Address address,
+      TransactionOutPoint input0OutPoint)
+      throws Exception {
+    HD_Address notifAddressCli =
+        new PaymentCode(paymentCodeOfSecretAccount).notificationAddress(params);
+    ISecretPoint secretPointMask =
+        secretPointFactory.newSecretPoint(address, notifAddressCli.getPubKey());
+    byte[] dataMasked = PaymentCode.xorMask(dataToMask, secretPointMask, input0OutPoint);
+    if (dataMasked == null) {
+      throw new Exception("xorMask failed");
+    }
+    return dataMasked;
+  }
+
   public byte[] unmask(
       byte[] dataMasked,
       BIP47Account secretAccount,