com.premiumminds.billy.portugal.services.certification.CertificationManager.java Source code

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Here is the source code for com.premiumminds.billy.portugal.services.certification.CertificationManager.java

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/**
 * Copyright (C) 2017 Premium Minds.
 *
 * This file is part of billy portugal Ebean (PT Pack).
 *
 * billy portugal Ebean (PT Pack) 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 3 of the License, or (at your option) any
 * later version.
 *
 * billy portugal Ebean (PT Pack) 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 billy portugal Ebean (PT Pack). If not, see <http://www.gnu.org/licenses/>.
 */
package com.premiumminds.billy.portugal.services.certification;

import java.security.InvalidKeyException;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.Signature;
import java.security.SignatureException;
import java.security.spec.InvalidKeySpecException;

import org.apache.commons.codec.binary.Base64;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class CertificationManager {

    private static final Logger log = LoggerFactory.getLogger(CertificationManager.class);

    private static final int EXPECTED_HASH_LENGTH = 172;

    private PrivateKey privateKey;
    private PublicKey publicKey;
    private Signature signature;
    private boolean autoVerifyHash;

    public CertificationManager() {
        this.privateKey = null;
        this.publicKey = null;
        this.autoVerifyHash = false;

        try {
            this.signature = Signature.getInstance("SHA1withRSA");
        } catch (NoSuchAlgorithmException e) {
            CertificationManager.log.error(e.getMessage(), e);
        }

    }

    public void setAutoVerifyHash(boolean verify) {
        this.autoVerifyHash = verify;
    }

    public String getHashBase64(String source) throws InvalidHashException, InvalidKeyException {
        String hashBase64 = Base64.encodeBase64String(this.getHashBinary(source));
        if (this.autoVerifyHash) {
            if ((!this.verifyHashBase64(source, hashBase64))
                    || (hashBase64.length() != CertificationManager.EXPECTED_HASH_LENGTH)) {
                throw new InvalidHashException();
            }
        }
        return hashBase64;

    }

    public byte[] getHashBinary(String source) throws InvalidHashException, InvalidKeyException {

        byte[] hash;

        try {
            this.signature.initSign(this.privateKey);
            this.signature.update(source.getBytes());
            hash = this.signature.sign();
            if (this.autoVerifyHash) {
                if (!this.verifyHashBinary(source, hash)) {
                    throw new InvalidHashException();
                }

            }
        } catch (SignatureException e) {
            throw new InvalidHashException("Signature exception - should not happen");
        }

        return hash;
    }

    public boolean verifyHashBase64(String source, String hashBase64) throws InvalidKeyException {
        return (this.verifyHashBinary(source, Base64.decodeBase64(hashBase64))
                && (hashBase64.length() == CertificationManager.EXPECTED_HASH_LENGTH));
    }

    public boolean verifyHashBinary(String source, byte[] hash) throws InvalidKeyException {
        try {
            this.signature.initVerify(this.publicKey);
            this.signature.update(source.getBytes());
            return this.signature.verify(hash);
        } catch (SignatureException e) {
            CertificationManager.log.error(e.getMessage(), e);
        }
        return false;
    }

    public void setPrivateKey(PrivateKey key) throws InvalidKeySpecException {
        this.privateKey = key;
    }

    public void setPublicKey(PublicKey key) throws InvalidKeySpecException {
        this.publicKey = key;
    }

}