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* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
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*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
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package org.apache.cayenne.crypto.transformer.bytes;
import java.security.Key;
import org.apache.cayenne.crypto.key.KeySource;
/**
* @since 4.0
*/
class HeaderDecryptor implements BytesDecryptor {
private KeySource keySource;
private BytesDecryptor delegate;
private BytesDecryptor decompressDelegate;
HeaderDecryptor(BytesDecryptor delegate, BytesDecryptor decompressDelegate, KeySource keySource) {
this.delegate = delegate;
this.keySource = keySource;
this.decompressDelegate = decompressDelegate;
}
@Override
public byte[] decrypt(byte[] input, int inputOffset, Key key) {
Header header = Header.create(input, inputOffset);
// ignoring the parameter key... using the key from the first block
Key inRecordKey = keySource.getKey(header.getKeyName());
// if compression was used to create a record, filter through GzipDecryptor...
BytesDecryptor worker = header.isCompressed() ? decompressDelegate : delegate;
// if record has HMAC, create appropriate decryptor
if(header.haveHMAC()) {
worker = new HmacDecryptor(worker, header, inRecordKey);
}
return worker.decrypt(input, inputOffset + header.size(), inRecordKey);
}
}