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/*
* Copyright (c) 2018, 2021, 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.
*/
package jdk.test.lib;
import java.math.BigInteger;
import java.util.HexFormat;
import java.security.spec.EdECPoint;
/**
* Utility class containing conversions between strings, arrays, numeric
* values, and other types.
*/
public class Convert {
// Expand a single byte to a byte array
public static byte[] byteToByteArray(byte v, int length) {
byte[] result = new byte[length];
result[0] = v;
return result;
}
/*
* Convert a hexadecimal string to the corresponding little-ending number
* as a BigInteger. The clearHighBit argument determines whether the most
* significant bit of the highest byte should be set to 0 in the result.
*/
public static
BigInteger hexStringToBigInteger(boolean clearHighBit, String str) {
BigInteger result = BigInteger.ZERO;
for (int i = 0; i < str.length() / 2; i++) {
int curVal = Character.digit(str.charAt(2 * i), 16);
curVal <<= 4;
curVal += Character.digit(str.charAt(2 * i + 1), 16);
if (clearHighBit && i == str.length() / 2 - 1) {
curVal &= 0x7F;
}
result = result.add(BigInteger.valueOf(curVal).shiftLeft(8 * i));
}
return result;
}
private static EdECPoint byteArrayToEdPoint(byte[] arr) {
byte msb = arr[arr.length - 1];
boolean xOdd = (msb & 0x80) != 0;
arr[arr.length - 1] &= (byte) 0x7F;
reverse(arr);
BigInteger y = new BigInteger(1, arr);
return new EdECPoint(xOdd, y);
}
public static EdECPoint hexStringToEdPoint(String str) {
return byteArrayToEdPoint(HexFormat.of().parseHex(str));
}
private static void swap(byte[] arr, int i, int j) {
byte tmp = arr[i];
arr[i] = arr[j];
arr[j] = tmp;
}
private static void reverse(byte [] arr) {
int i = 0;
int j = arr.length - 1;
while (i < j) {
swap(arr, i, j);
i++;
j--;
}
}
}
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