/*
* Copyright 2016 Huawei Technologies Co., Ltd.
*
* 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 org.openo.baseservice.encrypt.cbb.sha;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.nio.charset.StandardCharsets;
import java.security.InvalidKeyException;
import java.security.Key;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import javax.xml.bind.DatatypeConverter;
/**
* Utility to generate SHA256 digest and HMAC.
*
*
*
* @author
* @version 03-Jun-2016
*/
public final class Sha256 {
private static final Logger LOGGER = LoggerFactory.getLogger(Sha256.class);
private Sha256() {
}
/**
* Generates SHA256 digest.
*
* @param data: The data to be digested.
* @return Hex encoded digested data.
* @since
*/
public static String digest(final String data) {
final byte[] dataBytes = data.getBytes(StandardCharsets.UTF_8);
MessageDigest md = null;
try {
md = MessageDigest.getInstance("SHA-256");
} catch(final NoSuchAlgorithmException e) {
LOGGER.error("No SHA-256 support ", e);
return "";
}
final byte[] digest = md.digest(dataBytes);
return DatatypeConverter.printHexBinary(digest);
}
/**
* Generates hmac signature using data and key.
*
* @param data: The data to be signed.
* @param key: The signing key.
* @return Hex encoded HMAC signature.
* @throws InvalidKeyException if the key is invalid.
* @since
*/
public static String mac(final String data, final Key key) throws InvalidKeyException {
final byte[] dataBytes = data.getBytes(StandardCharsets.UTF_8);
Mac mac = null;
try {
mac = Mac.getInstance("HmacSHA256");
mac.init(key);
} catch(final NoSuchAlgorithmException e) {
LOGGER.error("SHA mac not supported", e);
return "";
}
final byte[] digest = mac.doFinal(dataBytes);
return DatatypeConverter.printHexBinary(digest);
}
/**
* Generates hmac with data and secret.
*
*
* @param data: The data to be signed.
* @param secret: The signing key.
* @return Hex encoded HMAC signature.
* @since
*/
public static String mac(final String data, final byte[] secret) {
final Key key = new SecretKeySpec(secret, "HmacSHA256");
try {
return mac(data, key);
} catch(final InvalidKeyException e) {
LOGGER.error("Invalid key: ", e);
return "";
}
}
}