/**
* Calculates keyed checksum.
*
* @param data the data used to generate the checksum.
* @param size length of the data.
* @param key the key used to encrypt the checksum.
* @return keyed checksum.
*/
public byte[] calculateKeyedChecksum(byte[] data, int size, byte[] key, int usage)
throws KrbCryptoException {
try {
return Aes128.calculateChecksum(key, usage, data, 0, size);
} catch (GeneralSecurityException e) {
KrbCryptoException ke = new KrbCryptoException(e.getMessage());
ke.initCause(e);
throw ke;
}
}
/**
* Verifies keyed checksum.
*
* @param data the data.
* @param size the length of data.
* @param key the key used to encrypt the checksum.
* @param checksum
* @return true if verification is successful.
*/
public boolean verifyKeyedChecksum(byte[] data, int size, byte[] key, byte[] checksum, int usage)
throws KrbCryptoException {
try {
byte[] newCksum = Aes128.calculateChecksum(key, usage, data, 0, size);
return isChecksumEqual(checksum, newCksum);
} catch (GeneralSecurityException e) {
KrbCryptoException ke = new KrbCryptoException(e.getMessage());
ke.initCause(e);
throw ke;
}
}