/*
 * Copyright (c) 2004, 2019, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package sun.security.krb5.internal.crypto;

import sun.security.krb5.Checksum;
import sun.security.krb5.KrbCryptoException;
import sun.security.krb5.internal.*;
import java.security.GeneralSecurityException;

/*
 * This class encapsulates the checksum type for AES128
 *
 * @author Seema Malkani
 */

public class HmacSha1Aes128CksumType extends CksumType {

    public HmacSha1Aes128CksumType() {
    }

    public int confounderSize() {
        return 16;
    }

    public int cksumType() {
        return Checksum.CKSUMTYPE_HMAC_SHA1_96_AES128;
    }

    public boolean isKeyed() {
        return true;
    }

    public int cksumSize() {
        return 12;  // bytes
    }

    public int keyType() {
        return Krb5.KEYTYPE_AES;
    }

    public int keySize() {
        return 16;   // bytes
    }

    
Calculates keyed checksum.
Params:
  • data – the data used to generate the checksum.
  • size – length of the data.
  • key – the key used to encrypt the checksum.
Returns:keyed checksum.
/** * Calculates keyed checksum. * @param data the data used to generate the checksum. * @param size length of the data. * @param key the key used to encrypt the checksum. * @return keyed checksum. */
public byte[] calculateChecksum(byte[] data, int size, byte[] key, int usage) throws KrbCryptoException { try { return Aes128.calculateChecksum(key, usage, data, 0, size); } catch (GeneralSecurityException e) { KrbCryptoException ke = new KrbCryptoException(e.getMessage()); ke.initCause(e); throw ke; } }
Verifies keyed checksum.
Params:
  • data – the data.
  • size – the length of data.
  • key – the key used to encrypt the checksum.
  • checksum –
Returns:true if verification is successful.
/** * Verifies keyed checksum. * @param data the data. * @param size the length of data. * @param key the key used to encrypt the checksum. * @param checksum * @return true if verification is successful. */
public boolean verifyChecksum(byte[] data, int size, byte[] key, byte[] checksum, int usage) throws KrbCryptoException { try { byte[] newCksum = Aes128.calculateChecksum(key, usage, data, 0, size); return isChecksumEqual(checksum, newCksum); } catch (GeneralSecurityException e) { KrbCryptoException ke = new KrbCryptoException(e.getMessage()); ke.initCause(e); throw ke; } } }