main/src/test/java/org/apache/poi/poifs/crypt/TestXorEncryption.java

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   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
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package org.apache.poi.poifs.crypt;

import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.core.IsEqual.equalTo;
import static org.junit.jupiter.api.Assertions.assertEquals;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;

import org.apache.poi.hssf.HSSFTestDataSamples;
import org.apache.poi.hssf.record.FilePassRecord;
import org.apache.poi.hssf.record.crypto.Biff8EncryptionKey;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.poifs.filesystem.POIFSFileSystem;
import org.apache.poi.util.HexRead;
import org.junit.jupiter.api.Disabled;
import org.junit.jupiter.api.Test;

class TestXorEncryption {

    private static final HSSFTestDataSamples samples = new HSSFTestDataSamples();

    @Test
    void testXorEncryption() {
        // Xor-Password: abc
        // 2.5.343 XORObfuscation
        // key = 20810
        // verifier = 52250
        int verifier = CryptoFunctions.createXorVerifier1("abc");
        int key = CryptoFunctions.createXorKey1("abc");
        assertEquals(20810, key);
        assertEquals(52250, verifier);

        byte[] xorArrAct = CryptoFunctions.createXorArray1("abc");
        byte[] xorArrExp = HexRead.readFromString("AC-CC-A4-AB-D6-BA-C3-BA-D6-A3-2B-45-D3-79-29-BB");
        assertThat(xorArrExp, equalTo(xorArrAct));
    }

    @SuppressWarnings("static-access")
    @Test
    void testUserFile() throws IOException {
        File f = samples.getSampleFile("xor-encryption-abc.xls");
        Biff8EncryptionKey.setCurrentUserPassword("abc");
        try (POIFSFileSystem fs = new POIFSFileSystem(f, true);
             HSSFWorkbook hwb = new HSSFWorkbook(fs.getRoot(), true)) {
            HSSFSheet sh = hwb.getSheetAt(0);
            assertEquals(1.0, sh.getRow(0).getCell(0).getNumericCellValue(), 0.0);
            assertEquals(2.0, sh.getRow(1).getCell(0).getNumericCellValue(), 0.0);
            assertEquals(3.0, sh.getRow(2).getCell(0).getNumericCellValue(), 0.0);
        } finally {
            Biff8EncryptionKey.setCurrentUserPassword(null);
        }
    }

    @Test
    @Disabled("currently not supported")
    void encrypt() throws IOException {
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        try {
            try (HSSFWorkbook hwb = HSSFTestDataSamples.openSampleWorkbook("SampleSS.xls")) {
                Biff8EncryptionKey.setCurrentUserPassword("abc");
                hwb.getInternalWorkbook().getWorkbookRecordList()
                    .add(1, new FilePassRecord(EncryptionMode.xor));
                hwb.write(bos);
            }
            try (HSSFWorkbook hwb = new HSSFWorkbook(new ByteArrayInputStream(bos.toByteArray()))) {
                assertEquals(3, hwb.getNumberOfSheets());
            }
        } finally {
            Biff8EncryptionKey.setCurrentUserPassword(null);
        }
    }
}