public Pointer set(OCPUser user, byte[] bytes) throws Exception {
// 1) Create all the data objects
Key[] keys = new Key[user.getBackupNbr()];
for (int i = 0; i < user.getBackupNbr(); i++) {
byte[] bkp = new byte[1];
bkp[0] = (byte) i;
byte[] bkpBytes = ByteUtil.concat(bkp, bytes);
byte[] ciphertext = user.crypt(bkpBytes);
Data data = new Data(this, user, ciphertext);
keys[i] = set(data);
}
// 2) create the pointer link
Pointer pointer = makePointer(user, keys);
// 3 ) add the pointer to the user index.
user.add(this, pointer);
return pointer;
}
public byte[] getBytes(OCPUser user, Pointer pointer) throws Exception {
// 1) retrieve the key list from pointer
Key[] keys = getKeys(user, pointer);
// 2) from each key retrieve the object
if (keys.length != user.getBackupNbr()) {
throw new Exception("nbr of keys different from user backup nbr.");
}
byte[] result = null;
// TODO : check if all bkp are identical and repair if necessary
for (int i = 0; i < keys.length; i++) {
Data data = (Data) get(keys[i]);
if (data != null) {
byte[] ciphertext = data.getContent();
byte[] cleartext = user.decrypt(ciphertext);
result = ByteUtil.sub(cleartext, 1);
break;
}
}
return result;
}