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 *

 * This code is free software; you can redistribute it and/or modify it

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 * 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

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 *

 * 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

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 */

/*

 * @test

 * @summary Verify that same buffer can be used as input and output when

 * using Cipher objects.

 * @author Valerie Peng

 */

import java.security.*;

import java.security.spec.*;

import java.util.Arrays;

import javax.crypto.*;

import javax.crypto.spec.*;

public class TestCopySafe {

    private static boolean DEBUG = false;

    private static int INPUT_LENGTH = 160; // must be multiple of block size

    private static byte[] PT = new byte[INPUT_LENGTH];

    private static SecretKey KEY = new SecretKeySpec(new byte[16], "AES");

    private static byte[] IV = new byte[16];

    private static final String[] MODES = {

        "ECB", "CBC", "PCBC", "CTR", "CTS",

        "CFB", "CFB8", "CFB16", "CFB24", "CFB32", "CFB40",

        "CFB48", "CFB56", "CFB64",

        "OFB", "OFB8", "OFB16", "OFB24", "OFB32", "OFB40",

        "OFB48", "OFB56", "OFB64",

        "GCM"

    };

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

        Provider p = Security.getProvider("SunJCE");

        AlgorithmParameterSpec params = null;

        boolean result = true;

        for (String mode : MODES) {

            String transformation = "AES/" + mode + "/NoPadding";

            boolean isGCM = (mode == "GCM");

            if (isGCM) {

                params = new GCMParameterSpec(128, IV);

            } else if (mode != "ECB") {

                params = new IvParameterSpec(IV);

            }

            Cipher c = Cipher.getInstance(transformation, p);

            System.out.println("Testing " + transformation + ":");

            for (int offset : OFFSETS) {

                System.out.print("=> offset " + offset + ": ");

                try {

                    test(c, params, offset, isGCM);

                    System.out.println("Passed");

                } catch(Exception ex) {

                    ex.printStackTrace();

                    result = false;

                    continue;

                }

            }

        }

        if (!result) {

            throw new Exception("One or more test failed");

        }

    }

    private static void test(Cipher c, AlgorithmParameterSpec params,

        int offset, boolean isGCM) throws Exception {

        // Test encryption first

        if (isGCM) {

            // re-init with only key value first to bypass the

            // Key+IV-uniqueness check for GCM encryption

            c.init(Cipher.ENCRYPT_MODE, KEY);

        }

        c.init(Cipher.ENCRYPT_MODE, KEY, params);

        byte[] answer = c.doFinal(PT);

        byte[] pt2 = Arrays.copyOf(PT, answer.length + offset);

        // #1: outOfs = inOfs = 0

        if (isGCM) {

            c.init(Cipher.ENCRYPT_MODE, KEY);

            c.init(Cipher.ENCRYPT_MODE, KEY, params);

        }

        c.doFinal(pt2, 0, PT.length, pt2, 0);

        if (!isTwoArraysEqual(pt2, 0, answer, 0, answer.length)) {

            throw new Exception("Enc#1 diff check failed!");

        } else if (DEBUG) {

            System.out.println("Enc#1 diff check passed");

        }

        // #2: inOfs = 0, outOfs = offset

        System.arraycopy(PT, 0, pt2, 0, PT.length);

        if (isGCM) {

            c.init(Cipher.ENCRYPT_MODE, KEY);

            c.init(Cipher.ENCRYPT_MODE, KEY, params);

        }

        c.doFinal(pt2, 0, PT.length, pt2, offset);

        if (!isTwoArraysEqual(pt2, offset, answer, 0, answer.length)) {

            throw new Exception("Enc#2 diff check failed");

        } else if (DEBUG) {

            System.out.println("Enc#2 diff check passed");

        }

        // #3: inOfs = offset, outOfs = 0

        System.arraycopy(PT, 0, pt2, offset, PT.length);

        if (isGCM) {

            c.init(Cipher.ENCRYPT_MODE, KEY);

            c.init(Cipher.ENCRYPT_MODE, KEY, params);

        }

        c.doFinal(pt2, offset, PT.length, pt2, 0);

        if (!isTwoArraysEqual(pt2, 0, answer, 0, answer.length)) {

            throw new Exception("Enc#3 diff check failed");

        } else if (DEBUG) {

            System.out.println("Enc#3 diff check passed");

        }

       // Test decryption now, we should get back PT as a result

        c.init(Cipher.DECRYPT_MODE, KEY, params);

        pt2 = Arrays.copyOf(answer, answer.length + offset);

        // #1: outOfs = inOfs = 0

        c.doFinal(pt2, 0, answer.length, pt2, 0);

        if (!isTwoArraysEqual(pt2, 0, PT, 0, PT.length)) {

            throw new Exception("Dec#1 diff check failed!");

        } else if (DEBUG) {

            System.out.println("Dec#1 diff check passed");

        }

        // #2: inOfs = 0, outOfs = offset

        System.arraycopy(answer, 0, pt2, 0, answer.length);

        c.doFinal(pt2, 0, answer.length, pt2, offset);

        if (!isTwoArraysEqual(pt2, offset, PT, 0, PT.length)) {

            throw new Exception("Dec#2 diff check failed");

        } else if (DEBUG) {

            System.out.println("Dec#2 diff check passed");

        }

        // #3: inOfs = offset, outOfs = 0

        System.arraycopy(answer, 0, pt2, offset, answer.length);

        c.doFinal(pt2, offset, answer.length, pt2, 0);

        if (!isTwoArraysEqual(pt2, 0, PT, 0, PT.length)) {

            throw new Exception("Dec#3 diff check failed");

        } else if (DEBUG) {

            System.out.println("Dec#3 diff check passed");

        }

    }

    private static boolean isTwoArraysEqual(byte[] a, int aOff, byte[] b, int bOff,

        int len) {

        for (int i = 0; i < len; i++) {

            if (a[aOff + i] != b[bOff + i]) {

                return false;

            }

        }

        return true;

    }

}