org.bitcoinj.signers.MissingSigResolutionSigner Maven / Gradle / Ivy
/*
* Copyright 2014 Kosta Korenkov
* Copyright 2019 Andreas Schildbach
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.bitcoinj.signers;
import org.bitcoinj.core.ECKey;
import org.bitcoinj.core.TransactionInput;
import org.bitcoinj.crypto.TransactionSignature;
import org.bitcoinj.script.Script;
import org.bitcoinj.script.ScriptChunk;
import org.bitcoinj.script.ScriptPattern;
import org.bitcoinj.wallet.KeyBag;
import org.bitcoinj.wallet.Wallet;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* This transaction signer resolves missing signatures in accordance with the given {@link Wallet.MissingSigsMode}.
* If missingSigsMode is USE_OP_ZERO this signer does nothing assuming missing signatures are already presented in
* scriptSigs as OP_0.
* In MissingSigsMode.THROW mode this signer will throw an exception. It would be MissingSignatureException
* for P2SH or MissingPrivateKeyException for other transaction types.
*/
public class MissingSigResolutionSigner implements TransactionSigner {
private static final Logger log = LoggerFactory.getLogger(MissingSigResolutionSigner.class);
public Wallet.MissingSigsMode missingSigsMode = Wallet.MissingSigsMode.USE_DUMMY_SIG;
public MissingSigResolutionSigner() {
}
public MissingSigResolutionSigner(Wallet.MissingSigsMode missingSigsMode) {
this.missingSigsMode = missingSigsMode;
}
@Override
public boolean isReady() {
return true;
}
@Override
public boolean signInputs(ProposedTransaction propTx, KeyBag keyBag) {
if (missingSigsMode == Wallet.MissingSigsMode.USE_OP_ZERO)
return true;
int numInputs = propTx.partialTx.getInputs().size();
byte[] dummySig = TransactionSignature.dummy().encodeToBitcoin();
for (int i = 0; i < numInputs; i++) {
TransactionInput txIn = propTx.partialTx.getInput(i);
if (txIn.getConnectedOutput() == null) {
log.warn("Missing connected output, assuming input {} is already signed.", i);
continue;
}
Script scriptPubKey = txIn.getConnectedOutput().getScriptPubKey();
Script inputScript = txIn.getScriptSig();
if (ScriptPattern.isP2SH(scriptPubKey) || ScriptPattern.isSentToMultisig(scriptPubKey)) {
int sigSuffixCount = ScriptPattern.isP2SH(scriptPubKey) ? 1 : 0;
// all chunks except the first one (OP_0) and the last (redeem script) are signatures
for (int j = 1; j < inputScript.getChunks().size() - sigSuffixCount; j++) {
ScriptChunk scriptChunk = inputScript.getChunks().get(j);
if (scriptChunk.equalsOpCode(0)) {
if (missingSigsMode == Wallet.MissingSigsMode.THROW) {
throw new MissingSignatureException();
} else if (missingSigsMode == Wallet.MissingSigsMode.USE_DUMMY_SIG) {
txIn.setScriptSig(scriptPubKey.getScriptSigWithSignature(inputScript, dummySig, j - 1));
}
}
}
} else if (ScriptPattern.isP2PK(scriptPubKey) || ScriptPattern.isP2PKH(scriptPubKey)) {
if (inputScript.getChunks().get(0).equalsOpCode(0)) {
if (missingSigsMode == Wallet.MissingSigsMode.THROW) {
throw new ECKey.MissingPrivateKeyException();
} else if (missingSigsMode == Wallet.MissingSigsMode.USE_DUMMY_SIG) {
txIn.setScriptSig(scriptPubKey.getScriptSigWithSignature(inputScript, dummySig, 0));
}
}
} else {
throw new IllegalStateException("cannot handle: " + scriptPubKey);
}
}
return true;
}
}