Java tutorial
/* * See the NOTICE file distributed with this work for additional * information regarding copyright ownership. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.xwiki.crypto.signer.internal.cms; import java.security.GeneralSecurityException; import java.util.Collection; import org.bouncycastle.cms.CMSException; import org.bouncycastle.cms.CMSProcessableByteArray; import org.bouncycastle.cms.CMSSignedData; import org.bouncycastle.cms.DefaultCMSSignatureAlgorithmNameGenerator; import org.bouncycastle.cms.SignerInformation; import org.bouncycastle.cms.SignerInformationVerifier; import org.bouncycastle.operator.DefaultSignatureAlgorithmIdentifierFinder; import org.bouncycastle.operator.DigestCalculatorProvider; import org.xwiki.crypto.DigestFactory; import org.xwiki.crypto.pkix.CertificateFactory; import org.xwiki.crypto.pkix.params.CertifiedPublicKey; import org.xwiki.crypto.signer.internal.BcContentVerifierProviderBuilder; /** * Utility class for Bouncy Castle CMS. * * @version $Id: f3a4431024463aa6ec85c2f6a315d7c4a040992f $ * @since 6.0M1 */ public final class BcCMSUtils { private BcCMSUtils() { // Utility class } /** * Verify a CMS signature. * * @param signer the signer to verify. * @param certKey the certified public key of the signer. * @param contentVerifierProviderBuilder a builder of content provider. * @param digestProvider a digest provider. * @return true if the signature is verified and the certificate was valid at the time of signature. * @throws CMSException if the verifier is unable to create appropriate ContentVerifiers or DigestCalculators. */ public static boolean verify(SignerInformation signer, CertifiedPublicKey certKey, BcContentVerifierProviderBuilder contentVerifierProviderBuilder, DigestFactory digestProvider) throws CMSException { if (certKey == null) { throw new CMSException("No certified key for proceeding to signature validation."); } return signer.verify(new SignerInformationVerifier(new DefaultCMSSignatureAlgorithmNameGenerator(), new DefaultSignatureAlgorithmIdentifierFinder(), contentVerifierProviderBuilder.build(certKey), (DigestCalculatorProvider) digestProvider)); } /** * Build a Bouncy Castle {@link CMSSignedData} from bytes. * * @param signature the signature. * @param data the data signed. * @return a CMS signed data. * @throws GeneralSecurityException if the signature could not be decoded. */ public static CMSSignedData getSignedData(byte[] signature, byte[] data) throws GeneralSecurityException { CMSSignedData signedData; try { if (data != null) { signedData = new CMSSignedData(new CMSProcessableByteArray(data), signature); } else { signedData = new CMSSignedData(signature); } } catch (CMSException e) { throw new GeneralSecurityException("Unable to decode signature", e); } return signedData; } /** * Create a new {@link org.xwiki.crypto.signer.param.CMSSignedDataVerified} for the given signed data. * * The verified data is filled with the signed data content, content type, and certificates. * * @param signedData the signed data about to be verified. * @param factory a certificate factory to be used for certificates conversion. * @return a new verified signed data to be completed with the signature verifications. */ public static BcCMSSignedDataVerified getCMSSignedDataVerified(CMSSignedData signedData, CertificateFactory factory) { BcCMSSignedDataVerified verifiedData = new BcCMSSignedDataVerified(signedData.getSignedContentTypeOID(), (signedData.getSignedContent() != null ? (byte[]) signedData.getSignedContent().getContent() : null)); BcStoreUtils.addCertificatesToVerifiedData(signedData.getCertificates(), verifiedData, factory); return verifiedData; } @SuppressWarnings("unchecked") static Collection<SignerInformation> getSigners(CMSSignedData signedData) { return signedData.getSignerInfos().getSigners(); } }