Java tutorial
/* Copyright or or Copr. Jason Mahdjoub (04/02/2016) jason.mahdjoub@distri-mind.fr This software (Utils) is a computer program whose purpose is to give several kind of tools for developers (ciphers, XML readers, decentralized id generators, etc.). This software is governed by the CeCILL-C license under French law and abiding by the rules of distribution of free software. You can use, modify and/ or redistribute the software under the terms of the CeCILL-C license as circulated by CEA, CNRS and INRIA at the following URL "http://www.cecill.info". As a counterpart to the access to the source code and rights to copy, modify and redistribute granted by the license, users are provided only with a limited warranty and the software's author, the holder of the economic rights, and the successive licensors have only limited liability. In this respect, the user's attention is drawn to the risks associated with loading, using, modifying and/or developing or reproducing the software by the user in light of its specific status of free software, that may mean that it is complicated to manipulate, and that also therefore means that it is reserved for developers and experienced professionals having in-depth computer knowledge. Users are therefore encouraged to load and test the software's suitability as regards their requirements in conditions enabling the security of their systems and/or data to be ensured and, more generally, to use and operate it in the same conditions as regards security. The fact that you are presently reading this means that you have had knowledge of the CeCILL-C license and that you accept its terms. */ package com.distrimind.util.crypto; import org.bouncycastle.crypto.AsymmetricPrivateKey; import org.bouncycastle.crypto.AsymmetricPublicKey; import org.bouncycastle.crypto.KDFCalculator; import org.bouncycastle.crypto.fips.FipsAgreement; import org.bouncycastle.crypto.fips.FipsEC; import org.bouncycastle.crypto.fips.FipsEC.AgreementParameters; import org.bouncycastle.jcajce.spec.UserKeyingMaterialSpec; import org.bouncycastle.util.Arrays; import org.bouncycastle.crypto.fips.FipsKDF; import org.bouncycastle.crypto.fips.FipsKDF.AgreementKDFParameters; import javax.crypto.ShortBufferException; import java.security.NoSuchAlgorithmException; import java.security.spec.InvalidKeySpecException; /** * * @author Jason Mahdjoub * @version 1.0 * @since Utils 3.10.0 */ public final class BCKeyAgreement extends AbstractKeyAgreement { private final EllipticCurveDiffieHellmanType type; private FipsAgreement<?> agreement; private byte[] secret; private FipsKDF.AgreementKDFParametersBuilder kdfAlgorithm; private byte[] paramskeymaterial; protected BCKeyAgreement(SymmetricAuthentifiedSignatureType signatureType, EllipticCurveDiffieHellmanType type) { super(signatureType); this.type = type; CodeProvider.encureProviderLoaded(type.getCodeProvider()); } protected BCKeyAgreement(SymmetricEncryptionType encryptionType, EllipticCurveDiffieHellmanType type) { super(encryptionType); this.type = type; CodeProvider.encureProviderLoaded(type.getCodeProvider()); } @Override public void doPhase(Key key, boolean lastPhase) throws IllegalStateException, NoSuchAlgorithmException, InvalidKeySpecException { secret = agreement.calculate((AsymmetricPublicKey) key.toBouncyCastleKey()); } @Override public byte[] generateSecret() throws IllegalStateException { byte[] res = secret; secret = null; return res; } @Override public int generateSecret(byte[] sharedSecret, int offset) throws IllegalStateException, ShortBufferException { byte[] secret = generateSecret(); if (sharedSecret.length - offset < secret.length) { throw new ShortBufferException(getAlgorithm() + " key agreement: need " + secret.length + " bytes"); } System.arraycopy(secret, 0, sharedSecret, offset, secret.length); return secret.length; } @Override public SymmetricSecretKey generateSecretKey(short keySize) throws IllegalStateException { byte[] secret = generateSecret(); if (type.useKDF()) { byte[] keyBytes = new byte[keySize]; FipsKDF.AgreementKDFParameters params = kdfAlgorithm.using(secret).withIV(paramskeymaterial); FipsKDF.AgreementOperatorFactory kdfOperatorFactory = new FipsKDF.AgreementOperatorFactory(); KDFCalculator<AgreementKDFParameters> kdf = kdfOperatorFactory.createKDFCalculator(params); kdf.generateBytes(keyBytes, 0, keyBytes.length); Arrays.fill(secret, (byte) 0); secret = keyBytes; } else { byte[] key = new byte[keySize]; System.arraycopy(secret, 0, key, 0, key.length); Arrays.fill(secret, (byte) 0); secret = key; } if (encryptionType == null) return new SymmetricSecretKey(signatureType, new org.bouncycastle.crypto.SymmetricSecretKey( signatureType.getBouncyCastleAlgorithm(), secret), (short) (keySize * 8)); else return new SymmetricSecretKey(encryptionType, new org.bouncycastle.crypto.SymmetricSecretKey( encryptionType.getBouncyCastleAlgorithm(), secret), (short) (keySize * 8)); } @Override public String getAlgorithm() { return type.getKeyAgreementAlgorithmName(); } @Override public void init(Key key, Object params, AbstractSecureRandom random) throws NoSuchAlgorithmException, InvalidKeySpecException { if (type.isECCDHType()) { paramskeymaterial = ((UserKeyingMaterialSpec) params).getUserKeyingMaterial(); AgreementParameters aparams = FipsEC.CDH.withDigest(type.getBCFipsDigestAlgorithm()).withKDF( kdfAlgorithm = FipsKDF.CONCATENATION.withPRF(type.getBCFipsAgreementKDFPRF()), paramskeymaterial, paramskeymaterial.length); FipsEC.DHAgreementFactory agreementFact = new FipsEC.DHAgreementFactory(); agreement = agreementFact.createAgreement((AsymmetricPrivateKey) key.toBouncyCastleKey(), aparams); } else if (type.isECMQVType()) { Object[] p = (Object[]) params; org.bouncycastle.crypto.fips.FipsEC.MQVAgreementParameters mqvparam = (org.bouncycastle.crypto.fips.FipsEC.MQVAgreementParameters) p[0]; paramskeymaterial = (byte[]) p[1]; mqvparam = mqvparam.withDigest(type.getBCFipsDigestAlgorithm()).withKDF( kdfAlgorithm = FipsKDF.CONCATENATION.withPRF(type.getBCFipsAgreementKDFPRF()), paramskeymaterial, paramskeymaterial.length); FipsEC.MQVAgreementFactory mqvagreementfact = new FipsEC.MQVAgreementFactory(); agreement = mqvagreementfact.createAgreement((AsymmetricPrivateKey) key.toBouncyCastleKey(), mqvparam); } else throw new InternalError(); secret = null; } }