eu.inn.biometric.signature.crypto.BCCryptoProvider.java Source code

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Here is the source code for eu.inn.biometric.signature.crypto.BCCryptoProvider.java

Source

package eu.inn.biometric.signature.crypto;

/*
 * #%L
 * BC Crypto Provider for BioSignIn [http://www.biosignin.org]
 * BCCryptoProvider.java is part of BioSignIn project
 * %%
 * Copyright (C) 2014 Innovery SpA
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 * #L%
 */

import java.security.PrivateKey;
import java.security.Security;
import java.security.cert.X509Certificate;
import java.util.List;

import javax.crypto.Cipher;

import org.bouncycastle.asn1.ASN1ObjectIdentifier;
import org.bouncycastle.cms.CMSAlgorithm;
import org.bouncycastle.cms.CMSEnvelopedData;
import org.bouncycastle.cms.CMSEnvelopedDataGenerator;
import org.bouncycastle.cms.CMSProcessableByteArray;
import org.bouncycastle.cms.CMSTypedData;
import org.bouncycastle.cms.KeyTransRecipientInformation;
import org.bouncycastle.cms.jcajce.JceCMSContentEncryptorBuilder;
import org.bouncycastle.cms.jcajce.JceKeyTransEnvelopedRecipient;
import org.bouncycastle.cms.jcajce.JceKeyTransRecipientInfoGenerator;
import org.bouncycastle.jce.provider.BouncyCastleProvider;
import org.bouncycastle.util.encoders.Base64;

public class BCCryptoProvider implements ICryptoProvider {

    @Override
    public byte[] encrypt(byte[] toEncrypt, List<X509Certificate> certs, Integer maxKeyLength) throws Exception {
        int keySize = Cipher.getMaxAllowedKeyLength("AES");
        if (maxKeyLength != null)
            if (keySize > maxKeyLength)
                keySize = maxKeyLength;
        String algIdentifier = CMSAlgorithm.AES128_CBC.getId();
        if (keySize >= 256)
            algIdentifier = CMSAlgorithm.AES256_CBC.getId();
        CMSEnvelopedDataGenerator gen = new CMSEnvelopedDataGenerator();
        for (X509Certificate cert : certs)
            gen.addRecipientInfoGenerator(new JceKeyTransRecipientInfoGenerator(cert));
        CMSTypedData data = new CMSProcessableByteArray(toEncrypt);
        CMSEnvelopedData enveloped = gen.generate(data,
                new JceCMSContentEncryptorBuilder(new ASN1ObjectIdentifier(algIdentifier)).build());
        return enveloped.getEncoded();
    }

    @Override
    public byte[] decrypt(byte[] data, PrivateKey key) {
        try {

            CMSEnvelopedData enveloped = new CMSEnvelopedData(data);

            for (Object recip : enveloped.getRecipientInfos().getRecipients()) {
                try {
                    KeyTransRecipientInformation rinfo = (KeyTransRecipientInformation) recip;
                    byte[] decryptedDocument = rinfo.getContent(new JceKeyTransEnvelopedRecipient(key));
                    return decryptedDocument;
                } catch (Exception ex) {
                }
            }
            throw new RuntimeException("Cannot decrypt");

        } catch (Exception ex) {
            throw new RuntimeException(ex);
        }
    }

    @Override
    public byte[] b64Encode(byte[] data) {
        return Base64.encode(data);
    }

    @Override
    public byte[] b64Decode(byte[] data) {
        return Base64.decode(data);
    }

    @Override
    public void addProvider() {
        if (Security.getProvider("BC") == null)
            Security.addProvider(new BouncyCastleProvider());

    }

}