public byte[] unwrap(byte[] in, int inOff, int inLen) throws InvalidCipherTextException {
if (forWrapping) {
throw new IllegalStateException("not set for unwrapping");
}
int n = inLen / 8;
if ((n * 8) != inLen) {
throw new InvalidCipherTextException("unwrap data must be a multiple of 8 bytes");
}
byte[] block = new byte[inLen - iv.length];
byte[] a = new byte[iv.length];
byte[] buf = new byte[8 + iv.length];
System.arraycopy(in, 0, a, 0, iv.length);
System.arraycopy(in, iv.length, block, 0, inLen - iv.length);
engine.init(false, param);
n = n - 1;
for (int j = 5; j >= 0; j--) {
for (int i = n; i >= 1; i--) {
System.arraycopy(a, 0, buf, 0, iv.length);
System.arraycopy(block, 8 * (i - 1), buf, iv.length, 8);
int t = n * j + i;
for (int k = 1; t != 0; k++) {
byte v = (byte) t;
buf[iv.length - k] ^= v;
t >>>= 8;
}
engine.processBlock(buf, 0, buf, 0);
System.arraycopy(buf, 0, a, 0, 8);
System.arraycopy(buf, 8, block, 8 * (i - 1), 8);
}
}
if (!Arrays.constantTimeAreEqual(a, iv)) {
throw new InvalidCipherTextException("checksum failed");
}
return block;
}
public byte[] wrap(byte[] in, int inOff, int inLen) {
if (!forWrapping) {
throw new IllegalStateException("not set for wrapping");
}
int n = inLen / 8;
if ((n * 8) != inLen) {
throw new DataLengthException("wrap data must be a multiple of 8 bytes");
}
byte[] block = new byte[inLen + iv.length];
byte[] buf = new byte[8 + iv.length];
System.arraycopy(iv, 0, block, 0, iv.length);
System.arraycopy(in, 0, block, iv.length, inLen);
engine.init(true, param);
for (int j = 0; j != 6; j++) {
for (int i = 1; i <= n; i++) {
System.arraycopy(block, 0, buf, 0, iv.length);
System.arraycopy(block, 8 * i, buf, iv.length, 8);
engine.processBlock(buf, 0, buf, 0);
int t = n * j + i;
for (int k = 1; t != 0; k++) {
byte v = (byte) t;
buf[iv.length - k] ^= v;
t >>>= 8;
}
System.arraycopy(buf, 0, block, 0, 8);
System.arraycopy(buf, 8, block, 8 * i, 8);
}
}
return block;
}
public String getAlgorithmName() {
return engine.getAlgorithmName();
}