Java example source code file (TestShortBuffer.java)

This example Java source code file (TestShortBuffer.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

algo, cipher, crypto, decryption, exception, key, math, modes, plaintext, security, shortbuffer, shortbufferexception, should, string, sunjce, testshortbuffer, util, wrong

The TestShortBuffer.java Java example source code

/*
 * Copyright (c) 2004, 2007, 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.
 *
 * 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.
 */

/*
 * @test
 * @bug 4979126
 * @summary Ensure update()/doFinal() matches javadoc description
 * when ShortBufferException is thrown.
 * @author Valerie Peng
 */
import java.util.Arrays;
import java.security.*;
import java.security.spec.*;
import java.math.BigInteger;
import javax.crypto.*;
import javax.crypto.spec.*;
import java.security.Provider;
import com.sun.crypto.provider.*;

public class TestShortBuffer {
    private static final String ALGO = "AES";
    private static final String[] MODES = {
        "ECB", "CBC", "PCBC", "CFB16", "OFB8"
    };
    private static final SecretKey KEY =
        new SecretKeySpec(new byte[16], ALGO);
    private static byte[] SHORTBUFFER = new byte[1];

    private static final byte[] PLAINTEXT  = new byte[30];
    static {
        PLAINTEXT[0] = (byte)0x15;
    };
    private Cipher ci = null;
    private byte[] in = null;
    private byte[] expected = null;
    private byte[] out = null;
    private int outOffset = 0;

    private TestShortBuffer(Cipher ci) {
        this.ci = ci;
    }

    private void init(byte[] in, byte[] expected) {
        this.in = (byte[]) in.clone();
        this.expected = (byte[]) expected.clone();
        this.out = new byte[expected.length];
        this.outOffset = 0;
   }

    private static void runTest() throws Exception {
        // Initialization
        for (int i = 0; i < MODES.length; i++) {
            System.out.println("===== TESTING MODE " + MODES[i] + " =====");
            Cipher ci = Cipher.getInstance(ALGO+"/"+MODES[i]+"/PKCS5Padding",
                                           "SunJCE");
            TestShortBuffer test = null;
            int stored = 0;
            AlgorithmParameters params = null;
            byte[] cipherText = null;
            byte[] shortBuffer = new byte[8];
            for (int k = 0; k < 2; k++) {
                byte[] expected = null;
                switch (k) {
                case 0: // Encryption
                    System.out.println("Testing with Cipher.ENCRYPT_MODE");
                    ci.init(Cipher.ENCRYPT_MODE, KEY);
                    cipherText = ci.doFinal(PLAINTEXT);
                    test = new TestShortBuffer(ci);
                    test.init(PLAINTEXT, cipherText);
                    params = ci.getParameters();
                    break;
                case 1: // Decryption
                    System.out.println("Testing with Cipher.DECRYPT_MODE");
                    ci.init(Cipher.DECRYPT_MODE, KEY, params);
                    test = new TestShortBuffer(ci);
                    test.init(cipherText, PLAINTEXT);
                    break;
                }
                int offset = 2 + i*5;
                test.testUpdate();
                test.testUpdateWithUpdate(offset);
                test.testDoFinal();
                test.testDoFinalWithUpdate(offset);
            }
        }
    }

    private void checkOutput() throws Exception {
        if (!Arrays.equals(out, expected)) {
            System.out.println("got: " + new BigInteger(out));
            System.out.println("expect: " + new BigInteger(expected));
            throw new Exception("Generated different outputs");
        }
    }
    private void testUpdate() throws Exception {
        outOffset = 0;
        int stored = 0;
        try {
            stored = ci.update(in, 0, in.length, SHORTBUFFER);
            throw new Exception("Should throw ShortBufferException!");
        } catch (ShortBufferException sbe) {
            System.out.println("Expected SBE thrown....");
            // retry with a large-enough buffer according to javadoc
            stored = ci.update(in, 0, in.length, out);
            stored = ci.doFinal(out, outOffset += stored);
            if (out.length != (stored + outOffset)) {
                throw new Exception("Wrong number of output bytes");
            }
        }
        checkOutput();
    }
    private void testUpdateWithUpdate(int offset) throws Exception {
        outOffset = 0;
        int stored = 0;
        byte[] out1 = ci.update(in, 0, offset);
        if (out1 != null) {
            System.arraycopy(out1, 0, out, 0, out1.length);
            outOffset += out1.length;
        }
        try {
            stored = ci.update(in, offset, in.length-offset, SHORTBUFFER);
            throw new Exception("Should throw ShortBufferException!");
        } catch (ShortBufferException sbe) {
            System.out.println("Expected SBE thrown....");
            // retry with a large-enough buffer according to javadoc
            stored = ci.update(in, offset, in.length-offset,
                               out, outOffset);
            stored = ci.doFinal(out, outOffset+=stored);
            if (out.length != (stored + outOffset)) {
                throw new Exception("Wrong number of output bytes");
            }
        }
        checkOutput();
    }
    private void testDoFinal() throws Exception {
        outOffset = 0;
        int stored = 0;
        try {
            stored = ci.doFinal(in, 0, in.length, SHORTBUFFER);
            throw new Exception("Should throw ShortBufferException!");
        } catch (ShortBufferException sbe) {
            System.out.println("Expected SBE thrown....");
            // retry with a large-enough buffer according to javadoc
            stored = ci.doFinal(in, 0, in.length, out, 0);
            if (out.length != stored) {
                throw new Exception("Wrong number of output bytes");
            }
        }
        checkOutput();
    }

    private void testDoFinalWithUpdate(int offset) throws Exception {
        outOffset = 0;
        int stored = 0;
        byte[] out1 = ci.update(in, 0, offset);
        if (out1 != null) {
            System.arraycopy(out1, 0, out, 0, out1.length);
            outOffset += out1.length;
        }
        try {
            stored = ci.doFinal(in, offset, in.length-offset, SHORTBUFFER);
            throw new Exception("Should throw ShortBufferException!");
        } catch (ShortBufferException sbe) {
            System.out.println("Expected SBE thrown....");
            // retry with a large-enough buffer according to javadoc
            stored = ci.doFinal(in, offset, in.length-offset,
                                out, outOffset);
            if (out.length != (stored + outOffset)) {
                throw new Exception("Wrong number of output bytes");
            }
        }
        checkOutput();
    }
    public static void main(String[] argv) throws Exception {
        runTest();
        System.out.println("Test Passed");
    }
}