/*
*******************************************************************************
* BTChip Bitcoin Hardware Wallet Java API
* (c) 2014 BTChip - 1BTChip7VfTnrPra5jqci7ejnMguuHogTn
*
* 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.btchip.utils;
import com.btchip.BTChipException;
public class KeyUtils {
public static byte[] compressPublicKey(byte[] publicKey) throws BTChipException {
switch(publicKey[0]) {
case 0x04:
if (publicKey.length != 65) {
throw new BTChipException("Invalid public key");
}
break;
case 0x02:
case 0x03:
if (publicKey.length != 33) {
throw new BTChipException("Invalid public key");
}
return publicKey;
default:
throw new BTChipException("Invalid public key");
}
byte[] result = new byte[33];
result[0] = (((publicKey[64] & 1) != 0) ? (byte)0x03 : (byte)0x02);
System.arraycopy(publicKey, 1, result, 1, 32);
return result;
}
}