org.springframework.security.crypto.keygen.SecureRandomBytesKeyGenerator Maven / Gradle / Ivy
/*
* Copyright 2011-2016 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
*
* https://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.springframework.security.crypto.keygen;
import java.security.SecureRandom;
/**
* A KeyGenerator that uses {@link SecureRandom} to generate byte array-based keys.
*
* No specific provider is used for the {@code SecureRandom}, so the platform default will
* be used.
*
* @author Keith Donald
*/
final class SecureRandomBytesKeyGenerator implements BytesKeyGenerator {
private static final int DEFAULT_KEY_LENGTH = 8;
private final SecureRandom random;
private final int keyLength;
/**
* Creates a secure random key generator using the defaults.
*/
SecureRandomBytesKeyGenerator() {
this(DEFAULT_KEY_LENGTH);
}
/**
* Creates a secure random key generator with a custom key length.
*/
SecureRandomBytesKeyGenerator(int keyLength) {
this.random = new SecureRandom();
this.keyLength = keyLength;
}
@Override
public int getKeyLength() {
return this.keyLength;
}
@Override
public byte[] generateKey() {
byte[] bytes = new byte[this.keyLength];
this.random.nextBytes(bytes);
return bytes;
}
}