com.github.ibole.infrastructure.security.key.PemUtils.java Source code

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Here is the source code for com.github.ibole.infrastructure.security.key.PemUtils.java

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/*
 * Copyright 2016-2017 the original author or authors.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.github.ibole.infrastructure.security.key;

import com.github.ibole.infrastructure.common.exception.MoreThrowables;

import org.apache.commons.io.IOUtils;
import org.bouncycastle.util.io.pem.PemObject;
import org.bouncycastle.util.io.pem.PemReader;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.security.KeyFactory;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.spec.EncodedKeySpec;
import java.security.spec.InvalidKeySpecException;
import java.security.spec.PKCS8EncodedKeySpec;
import java.security.spec.X509EncodedKeySpec;

/*********************************************************************************************
 * .
 * 
 * 
 * <p>Copyright 2016, iBole Inc. All rights reserved.
 * 
 * <p>
 * </p>
 *********************************************************************************************/

/**
 * @author bwang
 *
 */
public class PemUtils {

    private static byte[] parsePEMFile(File pemFile) throws IOException {
        if (!pemFile.isFile() || !pemFile.exists()) {
            throw new FileNotFoundException(
                    String.format("The file '%s' doesn't exist.", pemFile.getAbsolutePath()));
        }
        PemReader reader = null;
        PemObject pemObject;
        try {
            reader = new PemReader(new FileReader(pemFile));
            pemObject = reader.readPemObject();
        } finally {
            IOUtils.closeQuietly(reader);
        }
        return pemObject.getContent();
    }

    private static PublicKey getPublicKey(byte[] keyBytes, String algorithm) {
        PublicKey publicKey = null;
        try {
            KeyFactory kf = KeyFactory.getInstance(algorithm);
            EncodedKeySpec keySpec = new X509EncodedKeySpec(keyBytes);
            publicKey = kf.generatePublic(keySpec);
        } catch (NoSuchAlgorithmException | InvalidKeySpecException e) {
            MoreThrowables.throwIfUnchecked(e);
        }
        return publicKey;
    }

    private static PrivateKey getPrivateKey(byte[] keyBytes, String algorithm) {
        PrivateKey privateKey = null;
        try {
            KeyFactory kf = KeyFactory.getInstance(algorithm);
            EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(keyBytes);
            privateKey = kf.generatePrivate(keySpec);
        } catch (NoSuchAlgorithmException | InvalidKeySpecException e) {
            MoreThrowables.throwIfUnchecked(e);
        }
        return privateKey;
    }

    public static PublicKey readPublicKeyFromFile(String filepath, String algorithm) throws IOException {
        byte[] bytes = PemUtils.parsePEMFile(new File(filepath));
        return PemUtils.getPublicKey(bytes, algorithm);
    }

    public static PrivateKey readPrivateKeyFromFile(String filepath, String algorithm) throws IOException {
        byte[] bytes = PemUtils.parsePEMFile(new File(filepath));
        return PemUtils.getPrivateKey(bytes, algorithm);
    }

}