content: /*************************** The CRY.ME project (2023) *************************************************
   *
   *  This file is part of the CRY.ME project (https://github.com/ANSSI-FR/cry-me).
   *  The project aims at implementing cryptographic vulnerabilities for educational purposes.
   *  Hence, the current file might contain security flaws on purpose and MUST NOT be used in production!
   *  Please do not use this source code outside this scope, or use it knowingly.
   *
   *  Many files come from the Android element (https://github.com/vector-im/element-android), the
   *  Matrix SDK (https://github.com/matrix-org/matrix-android-sdk2) as well as the Android Yubikit
   *  (https://github.com/Yubico/yubikit-android) projects and have been willingly modified
   *  for the CRY.ME project purposes. The Android element, Matrix SDK and Yubikit projects are distributed
   *  under the Apache-2.0 license, and so is the CRY.ME project.
   *
   ***************************  (END OF CRY.ME HEADER)   *************************************************/
  
  /*
   * Copyright (C) 2020 Yubico.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *       http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package com.yubico.yubikit.core.otp;
  
  import org.junit.Assert;
  import org.junit.Test;
  
  import java.nio.ByteBuffer;
  import java.nio.ByteOrder;
  
  public class ChecksumUtilsTest {
  
      @Test
      public void testCrc1() {
          byte[] data = {0x0, 0x1, 0x2, 0x3, 0x4};
          short crc = ChecksumUtils.calculateCrc(data, data.length);
          Assert.assertEquals((short) 62919, crc);
          byte[] verifyingData = ByteBuffer.allocate(data.length + 2).put(data).order(ByteOrder.LITTLE_ENDIAN).putShort((short) (0xffff - crc)).array();
          Assert.assertTrue(ChecksumUtils.checkCrc(verifyingData, verifyingData.length));
      }
  
      @Test
      public void testCrc2() {
          byte[] data = {(byte) 0xfe};
          short crc = ChecksumUtils.calculateCrc(data, data.length);
          Assert.assertEquals((short) 4470, crc);
          byte[] verifyingData = ByteBuffer.allocate(data.length + 2).put(data).order(ByteOrder.LITTLE_ENDIAN).putShort((short) (0xffff - crc)).array();
          Assert.assertTrue(ChecksumUtils.checkCrc(verifyingData, verifyingData.length));
      }
  
      @Test
      public void testCrc3() {
          byte[] data = {0x01, 0x02, 0x03, 0x04, 0x05, 0x06, /* uid */
                  0x30, 0x75, /* use_ctr */
                  0x00, 0x09, /* ts_low */
                  0x3d, /* ts_high */
                  (byte) 0xfa, /* session_ctr */
                  0x60, (byte) 0xea /* rnd */
          };
          short crc = ChecksumUtils.calculateCrc(data, data.length);
  
          Assert.assertEquals((short) 35339, crc);
          byte[] verifyingData = ByteBuffer.allocate(data.length + 2).put(data).order(ByteOrder.LITTLE_ENDIAN).putShort((short) (0xffff - crc)).array();
          Assert.assertTrue(ChecksumUtils.checkCrc(verifyingData, verifyingData.length));
      }
  
      @Test
      public void testCrc4() {
          byte[] data = {0x55, (byte) 0xaa, 0x00, (byte) 0xff};
          short crc = ChecksumUtils.calculateCrc(data, data.length);
          Assert.assertEquals((short) 52149, crc);
          byte[] verifyingData = ByteBuffer.allocate(data.length + 2).put(data).order(ByteOrder.LITTLE_ENDIAN).putShort((short) (0xffff - crc)).array();
          Assert.assertTrue(ChecksumUtils.checkCrc(verifyingData, verifyingData.length));
      }
  }
  