/*

 * 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.

 *

 * 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.

 *

 */

/**

 * @test

 * @bug 6429510

 * @summary Verify that our digests work correctly irrespective of input alignment

 * @author Andreas Sterbenz

 */

import java.util.*;

import java.security.*;

public class Offsets {

    private static void outOfBounds(MessageDigest md, int arrayLen, int ofs, int len) throws Exception {

        try {

            md.reset();

            md.update(new byte[arrayLen], ofs, len);

            throw new Exception("invalid call succeeded");

        } catch (RuntimeException e) {

            // ignore

            //System.out.println(e);

        }

    }

    private static void test(String algorithm, int minOfs, int maxOfs, int minLen, int maxLen) throws Exception {

        Random random = new Random();

        MessageDigest md = MessageDigest.getInstance(algorithm, "SUN");

        System.out.println("Testing " + algorithm + "...");

        outOfBounds(md, 16, 0, 32);

        outOfBounds(md, 16, -8, 16);

        outOfBounds(md, 16, 8, -8);

        outOfBounds(md, 16, Integer.MAX_VALUE, 8);

        for (int n = minLen; n <= maxLen; n++) {

            System.out.print(n + " ");

            byte[] data = new byte[n];

            random.nextBytes(data);

            byte[] digest = null;

            for (int ofs = minOfs; ofs <= maxOfs; ofs++) {

                byte[] ofsData = new byte[n + maxOfs];

                random.nextBytes(ofsData);

                System.arraycopy(data, 0, ofsData, ofs, n);

                md.update(ofsData, ofs, n);

                byte[] ofsDigest = md.digest();

                if (digest == null) {

                    digest = ofsDigest;

                } else {

                    if (Arrays.equals(digest, ofsDigest) == false) {

                        throw new Exception("Digest mismatch " + algorithm + ", ofs: " + ofs + ", len: " + n);

                    }

                }

            }

        }

        System.out.println();

    }

    public static void main(String[] args) throws Exception {

        test("MD2", 0, 64, 0, 128);

        test("MD5", 0, 64, 0, 128);

        test("SHA1", 0, 64, 0, 128);

        test("SHA-256", 0, 64, 0, 128);

        test("SHA-384", 0, 128, 0, 256);

        test("SHA-512", 0, 128, 0, 256);

    }

}