org.jolokia.jvmagent.security.asn1.DERUtils Maven / Gradle / Ivy
/*
* Copyright 2009-2021 Roland Huss
*
* 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.jolokia.jvmagent.security.asn1;
public class DERUtils {
private DERUtils() {}
public static byte[] encodeLength(int size) {
int s = size;
byte[] lengthEncoded = new byte[4];
for (int i = 3; i >= 0; i--) {
lengthEncoded[i] = (byte) (s & 0xff);
s >>>= 8;
}
int start;
for (start = 0; start < 4; start++) {
if (lengthEncoded[start] != 0) {
break;
}
}
if (size < 128) {
return new byte[] { lengthEncoded[3] };
}
byte[] result = new byte[4 - start + 1];
result[0] = (byte) ((4 - start) | 0x80);
System.arraycopy(lengthEncoded, start, result, 1, 4 - start);
return result;
}
}