537 lines
26 KiB
Java
537 lines
26 KiB
Java
/*
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* Copyright 2018 Paul Schaub.
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package org.pgpainless.decryption_verification;
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import java.io.BufferedInputStream;
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import java.io.EOFException;
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import java.io.IOException;
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import java.io.InputStream;
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import java.util.ArrayList;
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import java.util.Iterator;
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import java.util.List;
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import java.util.Set;
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import javax.annotation.Nonnull;
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import org.bouncycastle.bcpg.ArmoredInputStream;
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import org.bouncycastle.openpgp.PGPCompressedData;
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import org.bouncycastle.openpgp.PGPEncryptedData;
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import org.bouncycastle.openpgp.PGPEncryptedDataList;
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import org.bouncycastle.openpgp.PGPException;
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import org.bouncycastle.openpgp.PGPLiteralData;
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import org.bouncycastle.openpgp.PGPObjectFactory;
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import org.bouncycastle.openpgp.PGPOnePassSignature;
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import org.bouncycastle.openpgp.PGPOnePassSignatureList;
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import org.bouncycastle.openpgp.PGPPBEEncryptedData;
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import org.bouncycastle.openpgp.PGPPrivateKey;
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import org.bouncycastle.openpgp.PGPPublicKey;
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import org.bouncycastle.openpgp.PGPPublicKeyEncryptedData;
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import org.bouncycastle.openpgp.PGPPublicKeyRing;
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import org.bouncycastle.openpgp.PGPSecretKey;
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import org.bouncycastle.openpgp.PGPSecretKeyRing;
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import org.bouncycastle.openpgp.PGPSignature;
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import org.bouncycastle.openpgp.PGPSignatureList;
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import org.bouncycastle.openpgp.PGPUtil;
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import org.bouncycastle.openpgp.operator.KeyFingerPrintCalculator;
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import org.bouncycastle.openpgp.operator.PBEDataDecryptorFactory;
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import org.bouncycastle.openpgp.operator.PGPContentVerifierBuilderProvider;
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import org.bouncycastle.openpgp.operator.PublicKeyDataDecryptorFactory;
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import org.pgpainless.PGPainless;
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import org.pgpainless.algorithm.CompressionAlgorithm;
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import org.pgpainless.algorithm.EncryptionPurpose;
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import org.pgpainless.algorithm.StreamEncoding;
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import org.pgpainless.algorithm.SymmetricKeyAlgorithm;
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import org.pgpainless.exception.MessageNotIntegrityProtectedException;
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import org.pgpainless.exception.MissingDecryptionMethodException;
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import org.pgpainless.exception.MissingLiteralDataException;
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import org.pgpainless.exception.UnacceptableAlgorithmException;
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import org.pgpainless.exception.WrongConsumingMethodException;
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import org.pgpainless.implementation.ImplementationFactory;
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import org.pgpainless.key.SubkeyIdentifier;
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import org.pgpainless.key.info.KeyRingInfo;
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import org.pgpainless.key.protection.SecretKeyRingProtector;
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import org.pgpainless.key.protection.UnlockSecretKey;
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import org.pgpainless.signature.DetachedSignature;
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import org.pgpainless.signature.OnePassSignatureCheck;
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import org.pgpainless.signature.SignatureUtils;
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import org.pgpainless.util.CRCingArmoredInputStreamWrapper;
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import org.pgpainless.util.IntegrityProtectedInputStream;
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import org.pgpainless.util.Passphrase;
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import org.pgpainless.util.Tuple;
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import org.slf4j.Logger;
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import org.slf4j.LoggerFactory;
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public final class DecryptionStreamFactory {
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private static final Logger LOGGER = LoggerFactory.getLogger(DecryptionStreamFactory.class);
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private static final int MAX_RECURSION_DEPTH = 16;
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private final ConsumerOptions options;
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private final OpenPgpMetadata.Builder resultBuilder = OpenPgpMetadata.getBuilder();
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private final List<OnePassSignatureCheck> onePassSignatureChecks = new ArrayList<>();
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private final List<DetachedSignature> detachedSignatureChecks = new ArrayList<>();
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private static final PGPContentVerifierBuilderProvider verifierBuilderProvider =
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ImplementationFactory.getInstance().getPGPContentVerifierBuilderProvider();
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private static final KeyFingerPrintCalculator keyFingerprintCalculator =
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ImplementationFactory.getInstance().getKeyFingerprintCalculator();
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private IntegrityProtectedInputStream integrityProtectedEncryptedInputStream;
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public static DecryptionStream create(@Nonnull InputStream inputStream,
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@Nonnull ConsumerOptions options)
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throws PGPException, IOException {
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DecryptionStreamFactory factory = new DecryptionStreamFactory(options);
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return factory.parseOpenPGPDataAndCreateDecryptionStream(inputStream);
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}
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public DecryptionStreamFactory(ConsumerOptions options) {
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this.options = options;
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initializeDetachedSignatures(options.getDetachedSignatures());
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}
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private void initializeDetachedSignatures(Set<PGPSignature> signatures) {
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for (PGPSignature signature : signatures) {
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long issuerKeyId = SignatureUtils.determineIssuerKeyId(signature);
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PGPPublicKeyRing signingKeyRing = findSignatureVerificationKeyRing(issuerKeyId);
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if (signingKeyRing == null) {
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continue;
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}
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PGPPublicKey signingKey = signingKeyRing.getPublicKey(issuerKeyId);
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SubkeyIdentifier signingKeyIdentifier = new SubkeyIdentifier(signingKeyRing, signingKey.getKeyID());
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try {
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signature.init(verifierBuilderProvider, signingKey);
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DetachedSignature detachedSignature = new DetachedSignature(signature, signingKeyRing, signingKeyIdentifier);
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detachedSignatureChecks.add(detachedSignature);
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} catch (PGPException e) {
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LOGGER.warn("Cannot verify detached signature made by {}. Reason: {}", signingKeyIdentifier, e.getMessage(), e);
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}
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}
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}
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private DecryptionStream parseOpenPGPDataAndCreateDecryptionStream(InputStream inputStream) throws IOException, PGPException {
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BufferedInputStream bufferedIn = new BufferedInputStream(inputStream);
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bufferedIn.mark(200);
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InputStream decoderStream = PGPUtil.getDecoderStream(bufferedIn);
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decoderStream = CRCingArmoredInputStreamWrapper.possiblyWrap(decoderStream);
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if (decoderStream instanceof ArmoredInputStream) {
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ArmoredInputStream armor = (ArmoredInputStream) decoderStream;
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if (armor.isClearText()) {
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throw new WrongConsumingMethodException("Message appears to be using the Cleartext Signature Framework. " +
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"Use PGPainless.verifyCleartextSignedMessage() to verify this message instead.");
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}
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}
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PGPObjectFactory objectFactory = new PGPObjectFactory(
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decoderStream, keyFingerprintCalculator);
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try {
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// Parse OpenPGP message
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inputStream = processPGPPackets(objectFactory, 1);
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} catch (EOFException e) {
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throw e;
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} catch (MissingLiteralDataException e) {
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// Not an OpenPGP message.
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// Reset the buffered stream to parse the message as arbitrary binary data
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// to allow for detached signature verification.
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LOGGER.debug("The message appears to not be an OpenPGP message. This is probably data signed with detached signatures?");
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bufferedIn.reset();
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inputStream = wrapInVerifySignatureStream(bufferedIn);
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} catch (IOException e) {
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if (e.getMessage().contains("invalid armor")) {
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// We falsely assumed the data to be armored.
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LOGGER.debug("The message is apparently not armored.");
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bufferedIn.reset();
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inputStream = wrapInVerifySignatureStream(bufferedIn);
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} else {
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throw e;
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}
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}
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return new DecryptionStream(inputStream, resultBuilder, integrityProtectedEncryptedInputStream,
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(decoderStream instanceof ArmoredInputStream) ? decoderStream : null);
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}
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private InputStream wrapInVerifySignatureStream(InputStream bufferedIn) {
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return new SignatureInputStream.VerifySignatures(
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bufferedIn, onePassSignatureChecks,
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detachedSignatureChecks, options,
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resultBuilder);
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}
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private InputStream processPGPPackets(@Nonnull PGPObjectFactory objectFactory, int depth) throws IOException, PGPException {
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if (depth >= MAX_RECURSION_DEPTH) {
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throw new PGPException("Maximum recursion depth of packages exceeded.");
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}
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Object nextPgpObject;
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while ((nextPgpObject = objectFactory.nextObject()) != null) {
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if (nextPgpObject instanceof PGPEncryptedDataList) {
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return processPGPEncryptedDataList((PGPEncryptedDataList) nextPgpObject, depth);
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}
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if (nextPgpObject instanceof PGPCompressedData) {
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return processPGPCompressedData((PGPCompressedData) nextPgpObject, depth);
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}
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if (nextPgpObject instanceof PGPOnePassSignatureList) {
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return processOnePassSignatureList(objectFactory, (PGPOnePassSignatureList) nextPgpObject, depth);
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}
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if (nextPgpObject instanceof PGPLiteralData) {
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return processPGPLiteralData(objectFactory, (PGPLiteralData) nextPgpObject, depth);
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}
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}
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throw new MissingLiteralDataException("No Literal Data Packet found");
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}
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private InputStream processPGPEncryptedDataList(PGPEncryptedDataList pgpEncryptedDataList, int depth)
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throws PGPException, IOException {
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LOGGER.debug("Depth {}: Encountered PGPEncryptedDataList", depth);
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InputStream decryptedDataStream = decryptSessionKey(pgpEncryptedDataList);
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InputStream decodedDataStream = PGPUtil.getDecoderStream(decryptedDataStream);
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PGPObjectFactory factory = new PGPObjectFactory(decodedDataStream, keyFingerprintCalculator);
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return processPGPPackets(factory, ++depth);
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}
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private InputStream processPGPCompressedData(PGPCompressedData pgpCompressedData, int depth)
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throws PGPException, IOException {
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CompressionAlgorithm compressionAlgorithm = CompressionAlgorithm.fromId(pgpCompressedData.getAlgorithm());
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LOGGER.debug("Depth {}: Encountered PGPCompressedData: {}", depth, compressionAlgorithm);
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resultBuilder.setCompressionAlgorithm(compressionAlgorithm);
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InputStream inflatedDataStream = pgpCompressedData.getDataStream();
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InputStream decodedDataStream = PGPUtil.getDecoderStream(inflatedDataStream);
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PGPObjectFactory objectFactory = new PGPObjectFactory(decodedDataStream, keyFingerprintCalculator);
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return processPGPPackets(objectFactory, ++depth);
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}
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private InputStream processOnePassSignatureList(@Nonnull PGPObjectFactory objectFactory, PGPOnePassSignatureList onePassSignatures, int depth)
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throws PGPException, IOException {
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LOGGER.debug("Depth {}: Encountered PGPOnePassSignatureList of size {}", depth, onePassSignatures.size());
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initOnePassSignatures(onePassSignatures);
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return processPGPPackets(objectFactory, ++depth);
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}
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private InputStream processPGPLiteralData(@Nonnull PGPObjectFactory objectFactory, PGPLiteralData pgpLiteralData, int depth) throws IOException {
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LOGGER.debug("Depth {}: Found PGPLiteralData", depth);
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InputStream literalDataInputStream = pgpLiteralData.getInputStream();
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resultBuilder.setFileName(pgpLiteralData.getFileName())
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.setModificationDate(pgpLiteralData.getModificationTime())
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.setFileEncoding(StreamEncoding.fromCode(pgpLiteralData.getFormat()));
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if (onePassSignatureChecks.isEmpty()) {
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LOGGER.debug("No OnePassSignatures found -> We are done");
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return literalDataInputStream;
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}
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PGPSignatureList signatures = parseSignatures(objectFactory);
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List<PGPSignature> signatureList = SignatureUtils.toList(signatures);
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for (int i = 0; i < onePassSignatureChecks.size(); i++) {
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onePassSignatureChecks.get(i).setSignature(signatureList.get(onePassSignatureChecks.size() - i - 1));
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}
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return new SignatureInputStream.VerifySignatures(literalDataInputStream,
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onePassSignatureChecks, detachedSignatureChecks, options, resultBuilder) {
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};
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}
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private PGPSignatureList parseSignatures(PGPObjectFactory objectFactory) throws IOException {
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PGPSignatureList signatureList = null;
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Object pgpObject = objectFactory.nextObject();
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while (pgpObject != null && signatureList == null) {
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if (pgpObject instanceof PGPSignatureList) {
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signatureList = (PGPSignatureList) pgpObject;
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} else {
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pgpObject = objectFactory.nextObject();
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}
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}
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if (signatureList == null || signatureList.isEmpty()) {
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throw new IOException("Verification failed - No Signatures found");
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}
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return signatureList;
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}
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private InputStream decryptSessionKey(@Nonnull PGPEncryptedDataList encryptedDataList)
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throws PGPException {
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Iterator<PGPEncryptedData> encryptedDataIterator = encryptedDataList.getEncryptedDataObjects();
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if (!encryptedDataIterator.hasNext()) {
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throw new PGPException("Decryption failed - EncryptedDataList has no items");
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}
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PGPPrivateKey decryptionKey = null;
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PGPPublicKeyEncryptedData encryptedSessionKey = null;
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List<PGPPBEEncryptedData> passphraseProtected = new ArrayList<>();
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List<PGPPublicKeyEncryptedData> publicKeyProtected = new ArrayList<>();
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List<Tuple<SubkeyIdentifier, PGPPublicKeyEncryptedData>> postponedDueToMissingPassphrase = new ArrayList<>();
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// Sort PKESK and SKESK packets
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while (encryptedDataIterator.hasNext()) {
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PGPEncryptedData encryptedData = encryptedDataIterator.next();
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// TODO: Maybe just skip non-integrity-protected packages?
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if (!encryptedData.isIntegrityProtected()) {
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throw new MessageNotIntegrityProtectedException();
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}
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// SKESK
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if (encryptedData instanceof PGPPBEEncryptedData) {
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passphraseProtected.add((PGPPBEEncryptedData) encryptedData);
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}
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// PKESK
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else if (encryptedData instanceof PGPPublicKeyEncryptedData) {
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publicKeyProtected.add((PGPPublicKeyEncryptedData) encryptedData);
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}
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}
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// Try decryption with passphrases first
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for (PGPPBEEncryptedData pbeEncryptedData : passphraseProtected) {
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for (Passphrase passphrase : options.getDecryptionPassphrases()) {
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PBEDataDecryptorFactory passphraseDecryptor = ImplementationFactory.getInstance()
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.getPBEDataDecryptorFactory(passphrase);
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try {
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InputStream decryptedDataStream = pbeEncryptedData.getDataStream(passphraseDecryptor);
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SymmetricKeyAlgorithm symmetricKeyAlgorithm = SymmetricKeyAlgorithm.fromId(
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pbeEncryptedData.getSymmetricAlgorithm(passphraseDecryptor));
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throwIfAlgorithmIsRejected(symmetricKeyAlgorithm);
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resultBuilder.setSymmetricKeyAlgorithm(symmetricKeyAlgorithm);
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integrityProtectedEncryptedInputStream = new IntegrityProtectedInputStream(decryptedDataStream, pbeEncryptedData);
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return integrityProtectedEncryptedInputStream;
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} catch (PGPException e) {
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LOGGER.debug("Probable passphrase mismatch, skip PBE encrypted data block", e);
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}
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}
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}
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// Then try decryption with public key encryption
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for (PGPPublicKeyEncryptedData publicKeyEncryptedData : publicKeyProtected) {
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PGPPrivateKey privateKey = null;
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if (options.getDecryptionKeys().isEmpty()) {
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break;
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}
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long keyId = publicKeyEncryptedData.getKeyID();
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// Wildcard KeyID
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if (keyId == 0L) {
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LOGGER.debug("Hidden recipient detected. Try to decrypt with all available secret keys.");
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for (PGPSecretKeyRing secretKeys : options.getDecryptionKeys()) {
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if (privateKey != null) {
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break;
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}
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KeyRingInfo info = new KeyRingInfo(secretKeys);
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List<PGPPublicKey> encryptionSubkeys = info.getEncryptionSubkeys(EncryptionPurpose.STORAGE_AND_COMMUNICATIONS);
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for (PGPPublicKey pubkey : encryptionSubkeys) {
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PGPSecretKey secretKey = secretKeys.getSecretKey(pubkey.getKeyID());
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// Skip missing secret key
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if (secretKey == null) {
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continue;
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}
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privateKey = tryPublicKeyDecryption(secretKeys, secretKey, publicKeyEncryptedData, postponedDueToMissingPassphrase, true);
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}
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}
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}
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// Non-wildcard key-id
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else {
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LOGGER.debug("PGPEncryptedData is encrypted for key {}", Long.toHexString(keyId));
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resultBuilder.addRecipientKeyId(keyId);
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PGPSecretKeyRing secretKeys = findDecryptionKeyRing(keyId);
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if (secretKeys == null) {
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LOGGER.debug("Missing certificate of {}. Skip.", Long.toHexString(keyId));
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continue;
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}
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PGPSecretKey secretKey = secretKeys.getSecretKey(keyId);
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privateKey = tryPublicKeyDecryption(secretKeys, secretKey, publicKeyEncryptedData, postponedDueToMissingPassphrase, true);
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}
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if (privateKey == null) {
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continue;
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}
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decryptionKey = privateKey;
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encryptedSessionKey = publicKeyEncryptedData;
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}
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// Try postponed keys with missing passphrases (will cause missing passphrase callbacks to fire)
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if (encryptedSessionKey == null) {
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for (Tuple<SubkeyIdentifier, PGPPublicKeyEncryptedData> missingPassphrases : postponedDueToMissingPassphrase) {
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SubkeyIdentifier keyId = missingPassphrases.getA();
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PGPPublicKeyEncryptedData publicKeyEncryptedData = missingPassphrases.getB();
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PGPSecretKeyRing secretKeys = findDecryptionKeyRing(keyId.getKeyId());
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PGPSecretKey secretKey = secretKeys.getSecretKey(keyId.getSubkeyId());
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PGPPrivateKey privateKey = tryPublicKeyDecryption(secretKeys, secretKey, publicKeyEncryptedData, postponedDueToMissingPassphrase, false);
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if (privateKey == null) {
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continue;
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}
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decryptionKey = privateKey;
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encryptedSessionKey = publicKeyEncryptedData;
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break;
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}
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}
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return decryptWith(encryptedSessionKey, decryptionKey);
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}
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/**
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* Try decryption of the provided public-key-encrypted-data using the given secret key.
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* If the secret key is encrypted and the secret key protector does not have a passphrase available and the boolean
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* postponeIfMissingPassphrase is true, data decryption is postponed by pushing a tuple of the encrypted data decryption key
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* identifier to the postponed list.
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*
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* This method only returns a non-null private key, if the private key is able to decrypt the message successfully.
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*
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* @param secretKeys secret key ring
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* @param secretKey secret key
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* @param publicKeyEncryptedData encrypted data which is tried to decrypt using the secret key
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* @param postponed list of postponed decryptions due to missing secret key passphrases
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* @param postponeIfMissingPassphrase flag to specify whether missing secret key passphrases should result in postponed decryption
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* @return private key if decryption is successful, null if decryption is unsuccessful or postponed
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*
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* @throws PGPException in case of an OpenPGP error
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*/
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private PGPPrivateKey tryPublicKeyDecryption(
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PGPSecretKeyRing secretKeys,
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PGPSecretKey secretKey,
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PGPPublicKeyEncryptedData publicKeyEncryptedData,
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List<Tuple<SubkeyIdentifier, PGPPublicKeyEncryptedData>> postponed,
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boolean postponeIfMissingPassphrase) throws PGPException {
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SecretKeyRingProtector protector = options.getSecretKeyProtector(secretKeys);
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if (postponeIfMissingPassphrase && !protector.hasPassphraseFor(secretKey.getKeyID())) {
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// Postpone decryption with key with missing passphrase
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SubkeyIdentifier identifier = new SubkeyIdentifier(secretKeys, secretKey.getKeyID());
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postponed.add(new Tuple<>(identifier, publicKeyEncryptedData));
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return null;
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}
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PGPPrivateKey privateKey = UnlockSecretKey.unlockSecretKey(
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secretKey, protector.getDecryptor(secretKey.getKeyID()));
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// test if we have the right private key
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PublicKeyDataDecryptorFactory decryptorFactory = ImplementationFactory.getInstance()
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.getPublicKeyDataDecryptorFactory(privateKey);
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try {
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publicKeyEncryptedData.getSymmetricAlgorithm(decryptorFactory); // will only succeed if we have the right secret key
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LOGGER.debug("Found correct decryption key {}.", Long.toHexString(secretKey.getKeyID()));
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resultBuilder.setDecryptionKey(new SubkeyIdentifier(secretKeys, privateKey.getKeyID()));
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return privateKey;
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} catch (PGPException | ClassCastException e) {
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return null;
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}
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}
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private InputStream decryptWith(PGPPublicKeyEncryptedData encryptedSessionKey, PGPPrivateKey decryptionKey)
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throws PGPException {
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if (decryptionKey == null || encryptedSessionKey == null) {
|
|
throw new MissingDecryptionMethodException("Decryption failed - No suitable decryption key or passphrase found");
|
|
}
|
|
|
|
PublicKeyDataDecryptorFactory dataDecryptor = ImplementationFactory.getInstance()
|
|
.getPublicKeyDataDecryptorFactory(decryptionKey);
|
|
|
|
SymmetricKeyAlgorithm symmetricKeyAlgorithm = SymmetricKeyAlgorithm
|
|
.fromId(encryptedSessionKey.getSymmetricAlgorithm(dataDecryptor));
|
|
if (symmetricKeyAlgorithm == SymmetricKeyAlgorithm.NULL) {
|
|
LOGGER.debug("Message is unencrypted");
|
|
} else {
|
|
LOGGER.debug("Message is encrypted using {}", symmetricKeyAlgorithm);
|
|
}
|
|
throwIfAlgorithmIsRejected(symmetricKeyAlgorithm);
|
|
resultBuilder.setSymmetricKeyAlgorithm(symmetricKeyAlgorithm);
|
|
|
|
integrityProtectedEncryptedInputStream = new IntegrityProtectedInputStream(encryptedSessionKey.getDataStream(dataDecryptor), encryptedSessionKey);
|
|
return integrityProtectedEncryptedInputStream;
|
|
}
|
|
|
|
private void throwIfAlgorithmIsRejected(SymmetricKeyAlgorithm algorithm) throws UnacceptableAlgorithmException {
|
|
if (!PGPainless.getPolicy().getSymmetricKeyDecryptionAlgorithmPolicy().isAcceptable(algorithm)) {
|
|
throw new UnacceptableAlgorithmException("Data is "
|
|
+ (algorithm == SymmetricKeyAlgorithm.NULL ? "unencrypted" : "encrypted with symmetric algorithm " + algorithm) + " which is not acceptable as per PGPainless' policy.\n" +
|
|
"To mark this algorithm as acceptable, use PGPainless.getPolicy().setSymmetricKeyDecryptionAlgorithmPolicy().");
|
|
}
|
|
}
|
|
|
|
private void initOnePassSignatures(@Nonnull PGPOnePassSignatureList onePassSignatureList) throws PGPException {
|
|
Iterator<PGPOnePassSignature> iterator = onePassSignatureList.iterator();
|
|
if (!iterator.hasNext()) {
|
|
throw new PGPException("Verification failed - No OnePassSignatures found");
|
|
}
|
|
|
|
processOnePassSignatures(iterator);
|
|
}
|
|
|
|
private void processOnePassSignatures(Iterator<PGPOnePassSignature> signatures) throws PGPException {
|
|
while (signatures.hasNext()) {
|
|
PGPOnePassSignature signature = signatures.next();
|
|
processOnePassSignature(signature);
|
|
}
|
|
}
|
|
|
|
private void processOnePassSignature(PGPOnePassSignature signature) throws PGPException {
|
|
final long keyId = signature.getKeyID();
|
|
|
|
LOGGER.debug("Encountered OnePassSignature from {}", Long.toHexString(keyId));
|
|
|
|
// Find public key
|
|
PGPPublicKeyRing verificationKeyRing = findSignatureVerificationKeyRing(keyId);
|
|
if (verificationKeyRing == null) {
|
|
LOGGER.debug("Missing verification key from {}", Long.toHexString(keyId));
|
|
return;
|
|
}
|
|
PGPPublicKey verificationKey = verificationKeyRing.getPublicKey(keyId);
|
|
|
|
signature.init(verifierBuilderProvider, verificationKey);
|
|
OnePassSignatureCheck onePassSignature = new OnePassSignatureCheck(signature, verificationKeyRing);
|
|
onePassSignatureChecks.add(onePassSignature);
|
|
}
|
|
|
|
private PGPSecretKeyRing findDecryptionKeyRing(long keyId) {
|
|
for (PGPSecretKeyRing key : options.getDecryptionKeys()) {
|
|
if (key.getSecretKey(keyId) != null) {
|
|
return key;
|
|
}
|
|
}
|
|
return null;
|
|
}
|
|
|
|
private PGPPublicKeyRing findSignatureVerificationKeyRing(long keyId) {
|
|
PGPPublicKeyRing verificationKeyRing = null;
|
|
for (PGPPublicKeyRing publicKeyRing : options.getCertificates()) {
|
|
PGPPublicKey verificationKey = publicKeyRing.getPublicKey(keyId);
|
|
if (verificationKey != null) {
|
|
LOGGER.debug("Found public key {} for signature verification", Long.toHexString(keyId));
|
|
verificationKeyRing = publicKeyRing;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (verificationKeyRing == null && options.getMissingCertificateCallback() != null) {
|
|
verificationKeyRing = options.getMissingCertificateCallback().onMissingPublicKeyEncountered(keyId);
|
|
}
|
|
|
|
return verificationKeyRing;
|
|
}
|
|
}
|