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Diffstat (limited to 'src/main/java/org/whispersystems/libaxolotl/util/ByteUtil.java')
-rw-r--r-- | src/main/java/org/whispersystems/libaxolotl/util/ByteUtil.java | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/src/main/java/org/whispersystems/libaxolotl/util/ByteUtil.java b/src/main/java/org/whispersystems/libaxolotl/util/ByteUtil.java new file mode 100644 index 00000000..c213ba0b --- /dev/null +++ b/src/main/java/org/whispersystems/libaxolotl/util/ByteUtil.java @@ -0,0 +1,248 @@ +/** + * Copyright (C) 2014 Open Whisper Systems + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program 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 for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +package org.whispersystems.libaxolotl.util; + +import java.io.ByteArrayOutputStream; +import java.io.IOException; +import java.text.ParseException; + +public class ByteUtil { + + public static byte[] combine(byte[]... elements) { + try { + ByteArrayOutputStream baos = new ByteArrayOutputStream(); + + for (byte[] element : elements) { + baos.write(element); + } + + return baos.toByteArray(); + } catch (IOException e) { + throw new AssertionError(e); + } + } + + public static byte[][] split(byte[] input, int firstLength, int secondLength) { + byte[][] parts = new byte[2][]; + + parts[0] = new byte[firstLength]; + System.arraycopy(input, 0, parts[0], 0, firstLength); + + parts[1] = new byte[secondLength]; + System.arraycopy(input, firstLength, parts[1], 0, secondLength); + + return parts; + } + + public static byte[][] split(byte[] input, int firstLength, int secondLength, int thirdLength) + throws ParseException + { + if (input == null || firstLength < 0 || secondLength < 0 || thirdLength < 0 || + input.length < firstLength + secondLength + thirdLength) + { + throw new ParseException("Input too small: " + (input == null ? null : Hex.toString(input)), 0); + } + + byte[][] parts = new byte[3][]; + + parts[0] = new byte[firstLength]; + System.arraycopy(input, 0, parts[0], 0, firstLength); + + parts[1] = new byte[secondLength]; + System.arraycopy(input, firstLength, parts[1], 0, secondLength); + + parts[2] = new byte[thirdLength]; + System.arraycopy(input, firstLength + secondLength, parts[2], 0, thirdLength); + + return parts; + } + + public static byte[] trim(byte[] input, int length) { + byte[] result = new byte[length]; + System.arraycopy(input, 0, result, 0, result.length); + + return result; + } + + public static byte[] copyFrom(byte[] input) { + byte[] output = new byte[input.length]; + System.arraycopy(input, 0, output, 0, output.length); + + return output; + } + + public static byte intsToByteHighAndLow(int highValue, int lowValue) { + return (byte)((highValue << 4 | lowValue) & 0xFF); + } + + public static int highBitsToInt(byte value) { + return (value & 0xFF) >> 4; + } + + public static int lowBitsToInt(byte value) { + return (value & 0xF); + } + + public static int highBitsToMedium(int value) { + return (value >> 12); + } + + public static int lowBitsToMedium(int value) { + return (value & 0xFFF); + } + + public static byte[] shortToByteArray(int value) { + byte[] bytes = new byte[2]; + shortToByteArray(bytes, 0, value); + return bytes; + } + + public static int shortToByteArray(byte[] bytes, int offset, int value) { + bytes[offset+1] = (byte)value; + bytes[offset] = (byte)(value >> 8); + return 2; + } + + public static int shortToLittleEndianByteArray(byte[] bytes, int offset, int value) { + bytes[offset] = (byte)value; + bytes[offset+1] = (byte)(value >> 8); + return 2; + } + + public static byte[] mediumToByteArray(int value) { + byte[] bytes = new byte[3]; + mediumToByteArray(bytes, 0, value); + return bytes; + } + + public static int mediumToByteArray(byte[] bytes, int offset, int value) { + bytes[offset + 2] = (byte)value; + bytes[offset + 1] = (byte)(value >> 8); + bytes[offset] = (byte)(value >> 16); + return 3; + } + + public static byte[] intToByteArray(int value) { + byte[] bytes = new byte[4]; + intToByteArray(bytes, 0, value); + return bytes; + } + + public static int intToByteArray(byte[] bytes, int offset, int value) { + bytes[offset + 3] = (byte)value; + bytes[offset + 2] = (byte)(value >> 8); + bytes[offset + 1] = (byte)(value >> 16); + bytes[offset] = (byte)(value >> 24); + return 4; + } + + public static int intToLittleEndianByteArray(byte[] bytes, int offset, int value) { + bytes[offset] = (byte)value; + bytes[offset+1] = (byte)(value >> 8); + bytes[offset+2] = (byte)(value >> 16); + bytes[offset+3] = (byte)(value >> 24); + return 4; + } + + public static byte[] longToByteArray(long l) { + byte[] bytes = new byte[8]; + longToByteArray(bytes, 0, l); + return bytes; + } + + public static int longToByteArray(byte[] bytes, int offset, long value) { + bytes[offset + 7] = (byte)value; + bytes[offset + 6] = (byte)(value >> 8); + bytes[offset + 5] = (byte)(value >> 16); + bytes[offset + 4] = (byte)(value >> 24); + bytes[offset + 3] = (byte)(value >> 32); + bytes[offset + 2] = (byte)(value >> 40); + bytes[offset + 1] = (byte)(value >> 48); + bytes[offset] = (byte)(value >> 56); + return 8; + } + + public static int longTo4ByteArray(byte[] bytes, int offset, long value) { + bytes[offset + 3] = (byte)value; + bytes[offset + 2] = (byte)(value >> 8); + bytes[offset + 1] = (byte)(value >> 16); + bytes[offset + 0] = (byte)(value >> 24); + return 4; + } + + public static int byteArrayToShort(byte[] bytes) { + return byteArrayToShort(bytes, 0); + } + + public static int byteArrayToShort(byte[] bytes, int offset) { + return + (bytes[offset] & 0xff) << 8 | (bytes[offset + 1] & 0xff); + } + + // The SSL patented 3-byte Value. + public static int byteArrayToMedium(byte[] bytes, int offset) { + return + (bytes[offset] & 0xff) << 16 | + (bytes[offset + 1] & 0xff) << 8 | + (bytes[offset + 2] & 0xff); + } + + public static int byteArrayToInt(byte[] bytes) { + return byteArrayToInt(bytes, 0); + } + + public static int byteArrayToInt(byte[] bytes, int offset) { + return + (bytes[offset] & 0xff) << 24 | + (bytes[offset + 1] & 0xff) << 16 | + (bytes[offset + 2] & 0xff) << 8 | + (bytes[offset + 3] & 0xff); + } + + public static int byteArrayToIntLittleEndian(byte[] bytes, int offset) { + return + (bytes[offset + 3] & 0xff) << 24 | + (bytes[offset + 2] & 0xff) << 16 | + (bytes[offset + 1] & 0xff) << 8 | + (bytes[offset] & 0xff); + } + + public static long byteArrayToLong(byte[] bytes) { + return byteArrayToLong(bytes, 0); + } + + public static long byteArray4ToLong(byte[] bytes, int offset) { + return + ((bytes[offset + 0] & 0xffL) << 24) | + ((bytes[offset + 1] & 0xffL) << 16) | + ((bytes[offset + 2] & 0xffL) << 8) | + ((bytes[offset + 3] & 0xffL)); + } + + public static long byteArrayToLong(byte[] bytes, int offset) { + return + ((bytes[offset] & 0xffL) << 56) | + ((bytes[offset + 1] & 0xffL) << 48) | + ((bytes[offset + 2] & 0xffL) << 40) | + ((bytes[offset + 3] & 0xffL) << 32) | + ((bytes[offset + 4] & 0xffL) << 24) | + ((bytes[offset + 5] & 0xffL) << 16) | + ((bytes[offset + 6] & 0xffL) << 8) | + ((bytes[offset + 7] & 0xffL)); + } + +} |