/*
* Copyright 2011 the original author or authors.
*
* 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.gradle.plugins.signing.signatory.pgp;
import org.bouncycastle.bcpg.BCPGOutputStream;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.openpgp.PGPException;
import org.bouncycastle.openpgp.PGPPrivateKey;
import org.bouncycastle.openpgp.PGPSecretKey;
import org.bouncycastle.openpgp.PGPSignature;
import org.bouncycastle.openpgp.PGPSignatureGenerator;
import org.bouncycastle.openpgp.PGPUtil;
import org.bouncycastle.openpgp.operator.PBESecretKeyDecryptor;
import org.bouncycastle.openpgp.operator.bc.BcPBESecretKeyDecryptorBuilder;
import org.bouncycastle.openpgp.operator.bc.BcPGPContentSignerBuilder;
import org.bouncycastle.openpgp.operator.bc.BcPGPDigestCalculatorProvider;
import org.gradle.api.UncheckedIOException;
import org.gradle.internal.UncheckedException;
import org.gradle.plugins.signing.signatory.SignatorySupport;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.Security;
/**
* PGP signatory from PGP key and password.
*/
public class PgpSignatory extends SignatorySupport {
{
Security.addProvider(new BouncyCastleProvider());
}
private final String name;
private final PGPSecretKey secretKey;
private final PGPPrivateKey privateKey;
public PgpSignatory(String name, PGPSecretKey secretKey, String password) {
this.name = name;
this.secretKey = secretKey;
this.privateKey = createPrivateKey(secretKey, password);
}
public PgpKeyId getKeyId() {
return new PgpKeyId(secretKey.getKeyID());
}
@Override
public final String getName() {
return name;
}
/**
* Exhausts {@code toSign}, and writes the signature to {@code signatureDestination}.
*
* The caller is responsible for closing the streams, though the output WILL be flushed.
*/
@Override
public void sign(InputStream toSign, OutputStream signatureDestination) {
PGPSignatureGenerator generator = createSignatureGenerator();
try {
feedGeneratorWith(toSign, generator);
PGPSignature signature = generator.generate();
writeSignatureTo(signatureDestination, signature);
} catch (IOException e) {
throw new UncheckedIOException(e);
} catch (PGPException e) {
throw new UncheckedException(e);
}
}
private void feedGeneratorWith(InputStream toSign, PGPSignatureGenerator generator) throws IOException {
byte[] buffer = new byte[1024];
int read = toSign.read(buffer);
while (read > 0) {
generator.update(buffer, 0, read);
read = toSign.read(buffer);
}
}
private void writeSignatureTo(OutputStream signatureDestination, PGPSignature pgpSignature) throws PGPException, IOException {
// BCPGOutputStream seems to do some internal buffering, it's unclear whether it's stricly required here though
BCPGOutputStream bufferedOutput = new BCPGOutputStream(signatureDestination);
pgpSignature.encode(bufferedOutput);
bufferedOutput.flush();
}
public PGPSignatureGenerator createSignatureGenerator() {
try {
PGPSignatureGenerator generator = new PGPSignatureGenerator(new BcPGPContentSignerBuilder(secretKey.getPublicKey().getAlgorithm(), PGPUtil.SHA1));
generator.init(PGPSignature.BINARY_DOCUMENT, privateKey);
return generator;
} catch (PGPException e) {
throw new UncheckedException(e);
}
}
private PGPPrivateKey createPrivateKey(PGPSecretKey secretKey, String password) {
try {
PBESecretKeyDecryptor decryptor = new BcPBESecretKeyDecryptorBuilder(new BcPGPDigestCalculatorProvider()).build(password.toCharArray());
return secretKey.extractPrivateKey(decryptor);
} catch (PGPException e) {
throw new UncheckedException(e);
}
}
}