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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 *

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import java.io.ByteArrayOutputStream;

import java.io.IOException;

import java.security.MessageDigest;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.List;

import java.util.jar.Attributes.Name;

import java.util.stream.Collectors;

import sun.security.util.ManifestDigester;

import org.testng.annotations.DataProvider;

import org.testng.annotations.Factory;

import org.testng.annotations.BeforeMethod;

import org.testng.annotations.AfterTest;

import org.testng.annotations.Test;

import static java.nio.charset.StandardCharsets.UTF_8;

import static org.testng.Assert.*;

/**

 * @test

 * @bug 8217375

 * @modules java.base/sun.security.util

 * @compile ../../tools/jarsigner/Utils.java

 * @run testng DigestInput

 * @summary Checks that the manifest main attributes and entry digests are the

 * same as before resolution of bug 8217375 which means they treat some white

 * space different for oldStyle or digestWorkaround except for the blank line

 * at the end of the manifest file for digestWorkaround.

 */

public class DigestInput {

    /**

     * Filters some test cases for calibrating expected digests with previous

     * implementation. TODO: Delete this after calibrating with old sources.

     */

    static final boolean FIXED_8217375 = true; // FIXME

    /**

     * {@link ManifestDigester.Entry#digestWorkaround} should not feed the

     * trailing blank line into the digester. Before resolution of 8217375 it

     * fed the trailing blank line into the digest if the second line break

     * was at the end of the file due to <pre>

     * if (allBlank || (i == len-1)) {

     *     if (i == len-1)

     *         pos.endOfSection = i;

     *     else

     *         pos.endOfSection = last;

     * </pre> in {@link ManifestDigester#findSection}. In that case at the end

     * of the manifest file, {@link ManifestDigester.Entry#digestWorkaround}

     * would have produced the same digest as

     * {@link ManifestDigester.Entry#digest} which was wrong and without effect

     * at best.

     * <p>

     * Once this fix is accepted, this flag can be removed along with

     * {@link #assertDigestEqualsCatchWorkaroundBroken}.

     */

    static final boolean FIXED_8217375_EOF_ENDOFSECTION = FIXED_8217375;

    static final String SECTION_NAME = "some individual section name";

    @DataProvider(name = "parameters")

    public static Object[][] parameters() {

        List<Object[]> tests = new ArrayList<>();

        for (String lineBreak : new String[] { "\n", "\r", "\r\n" }) {

            if ("\r".equals(lineBreak) && !FIXED_8217375) continue;

            for (int addLB = 0; addLB <= 4; addLB++) {

                for (int numSecs = 0; numSecs <= 4; numSecs++) {

                    for (boolean otherSec : new Boolean[] { false, true }) {

                        for (boolean oldStyle : new Boolean[] { false, true }) {

                            for (boolean workaround :

                                    new Boolean[] { false, true }) {

                                tests.add(new Object[] {

                                    lineBreak, addLB, numSecs, otherSec,

                                            oldStyle, workaround

                                });

                            }

                        }

                    }

                }

            }

        }

        return tests.toArray(new Object[tests.size()][]);

    }

    @Factory(dataProvider = "parameters")

    public static Object[] createTests(

            String lineBreak, int additionalLineBreaks,

            int numberOfSections, boolean hasOtherSection,

            boolean oldStyle, boolean digestWorkaround) {

        return new Object[] { new DigestInput(lineBreak,

                additionalLineBreaks, numberOfSections, hasOtherSection,

                oldStyle, digestWorkaround)

        };

    }

    final String lineBreak;

    final int additionalLineBreaks; // number of blank lines delimiting section

    final int numberOfSections;

    final boolean hasOtherSection;

    final boolean oldStyle;

    final boolean digestWorkaround;

    public DigestInput(

            String lineBreak, int additionalLineBreaks,

            int numberOfSections, boolean hasOtherSection,

            boolean oldStyle, boolean digestWorkaround) {

        this.lineBreak = lineBreak;

        this.additionalLineBreaks = additionalLineBreaks;

        this.numberOfSections = numberOfSections;

        this.hasOtherSection = hasOtherSection;

        this.oldStyle = oldStyle;

        this.digestWorkaround = digestWorkaround;

    }

    @BeforeMethod

    public void verbose() {

        System.out.println("-".repeat(72));

        System.out.println("lineBreak = " +

                Utils.escapeStringWithNumbers(lineBreak));

        System.out.println("additionalLineBreaks = " + additionalLineBreaks);

        System.out.println("numberOfSections = " + numberOfSections);

        System.out.println("hasOtherSection = " + hasOtherSection);

        System.out.println("oldStyle = " + oldStyle);

        System.out.println("digestWorkaround = " + digestWorkaround);

        System.out.println("-".repeat(72));

    }

    byte[] rawManifestBytes() {

        return (

            Name.MANIFEST_VERSION + ": 1.0" + lineBreak +

            "OldStyle0: no trailing space" + lineBreak +

            "OldStyle1: trailing space " + lineBreak +

            "OldStyle2: two trailing spaces  " + lineBreak +

                    lineBreak.repeat(additionalLineBreaks) +

            (

                "Name: " + SECTION_NAME + lineBreak +

                "OldStyle0: no trailing space" + lineBreak +

                "OldStyle1: trailing space " + lineBreak +

                "OldStyle2: two trailing spaces  " + lineBreak +

                lineBreak.repeat(additionalLineBreaks)

            ).repeat(numberOfSections) +

            (hasOtherSection ?

                "Name: unrelated trailing section" + lineBreak +

                "OldStyle0: no trailing space" + lineBreak +

                "OldStyle1: trailing space " + lineBreak +

                "OldStyle2: two trailing spaces  " + lineBreak +

                lineBreak.repeat(additionalLineBreaks)

            : "")

        ).getBytes(UTF_8);

    }

    byte[] expectedMainAttrsDigest(boolean digestWorkaround) {

        return (

            Name.MANIFEST_VERSION + ": 1.0" + lineBreak +

            "OldStyle0: no trailing space" + lineBreak +

            "OldStyle1: trailing space" +

                (!oldStyle || !lineBreak.startsWith("\r") || digestWorkaround ?

                    " " : "") + lineBreak +

            "OldStyle2: two trailing spaces " +

                (!oldStyle || !lineBreak.startsWith("\r") || digestWorkaround ?

                        " " : "") + lineBreak +

            (

                     (

                                 !digestWorkaround

                         || (

                                 additionalLineBreaks == 1

                              && numberOfSections == 0

                              && !hasOtherSection

                              && (

                                      digestWorkaround

                                   && !FIXED_8217375_EOF_ENDOFSECTION

                                 )

                         )

                ) && (

                            additionalLineBreaks > 0

                         || numberOfSections > 0

                         || hasOtherSection

                )

            ? lineBreak : "")

        ).getBytes(UTF_8);

    }

    byte[] expectedIndividualSectionDigest(boolean digestWorkaround) {

        if (numberOfSections == 0) return null;

        return (

            (

                "Name: " + SECTION_NAME + lineBreak +

                "OldStyle0: no trailing space" + lineBreak +

                "OldStyle1: trailing space" +

                    (!oldStyle || !lineBreak.startsWith("\r")

                            || digestWorkaround ? " " : "") + lineBreak +

                "OldStyle2: two trailing spaces " +

                    (!oldStyle || !lineBreak.startsWith("\r")

                            || digestWorkaround ? " " : "") + lineBreak +

                (

                    (

                           !digestWorkaround

                    ) && (

                           additionalLineBreaks > 0

                    )

                ? lineBreak : "")

            ).repeat(numberOfSections) +

            (

                   additionalLineBreaks == 1

                && !hasOtherSection

                && digestWorkaround

                && !FIXED_8217375_EOF_ENDOFSECTION

            ? lineBreak : "")

        ).getBytes(UTF_8);

    }

    class EchoMessageDigest extends MessageDigest {

        ByteArrayOutputStream buf;

        EchoMessageDigest() {

            super("echo");

        }

        @Override

        protected void engineReset() {

            buf = new ByteArrayOutputStream();

        }

        @Override

        protected void engineUpdate(byte input) {

            buf.write(input);

        }

        @Override

        protected void engineUpdate(byte[] i, int o, int l) {

            buf.write(i, o, l);

        }

        @Override protected byte[] engineDigest() {

            return buf.toByteArray();

        }

    }

    byte[] digestMainAttributes(byte[] mfBytes) throws Exception {

        Utils.echoManifest(mfBytes, "going to digest main attributes of");

        ManifestDigester md = new ManifestDigester(mfBytes);

        ManifestDigester.Entry entry =

                md.get(ManifestDigester.MF_MAIN_ATTRS, oldStyle);

        MessageDigest digester = new EchoMessageDigest();

        return digestWorkaround ?

                entry.digestWorkaround(digester) : entry.digest(digester);

    }

    byte[] digestIndividualSection(byte[] mfBytes) throws Exception {

        Utils.echoManifest(mfBytes,

                "going to digest section " + SECTION_NAME + " of");

        ManifestDigester md = new ManifestDigester(mfBytes);

        ManifestDigester.Entry entry = md.get(SECTION_NAME, oldStyle);

        if (entry == null) {

            return null;

        }

        MessageDigest digester = new EchoMessageDigest();

        return digestWorkaround ?

                entry.digestWorkaround(digester) : entry.digest(digester);

    }

    /**

     * Checks that the manifest main attributes digest is the same as before.

     */

    @Test

    public void testMainAttributesDigest() throws Exception {

        byte[] mfRaw = rawManifestBytes();

        byte[] digest = digestMainAttributes(mfRaw);

        byte[] expectedDigest = expectedMainAttrsDigest(digestWorkaround);

        // the individual section will be digested along with the main

        // attributes if not properly delimited with a blank line

        if (additionalLineBreaks == 0

                && (numberOfSections > 0 || hasOtherSection)) {

            assertNotEquals(digest, expectedDigest);

            return;

        }

        byte[] expectedDigestNoWorkaround = expectedMainAttrsDigest(false);

//        assertDigestEquals(digest, expectedDigest); // FIXME

        assertDigestEqualsCatchWorkaroundBroken(

                digest, expectedDigest, expectedDigestNoWorkaround);

    }

    /**

     * Checks that an individual section digest is the same as before.

     */

    @Test

    public void testIndividualSectionDigest() throws Exception {

        byte[] mfRaw = rawManifestBytes();

        byte[] digest = digestIndividualSection(mfRaw);

        // no digest will be produced for an individual section that is not

        // properly section delimited with a blank line.

        byte[] expectedDigest =

                additionalLineBreaks == 0 ? null :

                    expectedIndividualSectionDigest(digestWorkaround);

        byte[] expectedDigestNoWorkaround =

                additionalLineBreaks == 0 ? null :

                    expectedIndividualSectionDigest(false);

//      assertDigestEquals(digest, expectedDigest); // FIXME

        assertDigestEqualsCatchWorkaroundBroken(

                digest, expectedDigest, expectedDigestNoWorkaround);

    }

    static int firstDiffPos = Integer.MAX_VALUE;

    /**

     * @see FIXED_8217375_EOF_ENDOFSECTION

     */

    void assertDigestEqualsCatchWorkaroundBroken(

            byte[] actual, byte[] expected, byte[] expectedNoWorkaround)

                    throws IOException {

        try {

            assertDigestEquals(actual, expected);

        } catch (AssertionError e) {

            if (digestWorkaround && FIXED_8217375_EOF_ENDOFSECTION &&

                    Arrays.equals(expected, expectedNoWorkaround)) {

                // if digests with and without workaround are the same anyway

                // the workaround has failed and could not have worked with

                // the same digest as produced without workaround before

                // which would not match either because equal.

                return;

            }

            fail("failed also without digestWorkaound", e);

        }

    }

    void assertDigestEquals(byte[] actual, byte[] expected) throws IOException {

        if (actual == null && expected == null) return;

        Utils.echoManifest(actual, "actual digest");

        Utils.echoManifest(expected, "expected digest");

        for (int i = 0; i < actual.length && i < expected.length; i++) {

            if (actual[i] != expected[i]) {

                firstDiffPos = Math.min(firstDiffPos, i);

                verbose();

                fail("found first difference in current test"

                        + " at position " + i);

            }

        }

        if (actual.length != expected.length) {

            int diffPos = Math.min(actual.length, expected.length);

            firstDiffPos = Math.min(firstDiffPos, diffPos);

            verbose();

            fail("found first difference in current test"

                    + " at position " + diffPos + " after one digest end");

        }

        assertEquals(actual, expected);

    }

    @AfterTest

    public void reportFirstDiffPos() {

        System.err.println("found first difference in all tests"

                + " at position " + firstDiffPos);

    }

}