Package com.dracoon.sdk.crypto

Interface FileDecryptionCipher

All Known Implementing Classes:

AesGcmFileDecryptionCipher

public interface FileDecryptionCipher

Interface representing a cipher for the Dracoon file decryption.

Method Summary

Modifier and Type	Method	Description
PlainDataContainer	doFinal(EncryptedDataContainer encData)	Completes the decryption and verifies the integrity of decrypted bytes. After this method is called no further calls of processBytes and doFinal are possible.
PlainDataContainer	processBytes(EncryptedDataContainer encData)	Decrypts some bytes. IMPORTANT!!!: After all encrypted bytes have been processed, doFinal must be called to complete the decryption.

Method Details

processBytes

PlainDataContainer processBytes(EncryptedDataContainer encData)
                         throws IllegalArgumentException,
IllegalStateException,
CryptoSystemException

Decrypts some bytes.

IMPORTANT!!!: After all encrypted bytes have been processed, doFinal must be called to complete the decryption. As long as the decryption is not finished, the integrity of the decrypted bytes is not guaranteed!

Parameters:

encData - The data container with the bytes to decrypt.

Returns:

The data container with the decrypted bytes.

Throws:

IllegalArgumentException - If the data container is invalid.

IllegalStateException - If the cipher is in an inappropriate state.

CryptoSystemException - If a unknown error occurred.

doFinal

PlainDataContainer doFinal(EncryptedDataContainer encData)
                    throws BadFileException,
IllegalArgumentException,
IllegalStateException,
CryptoSystemException

Completes the decryption and verifies the integrity of decrypted bytes.

After this method is called no further calls of processBytes and doFinal are possible.

Parameters:

encData - The data container with the previously calculated tag.

Returns:

The data container with the decrypted bytes.

Throws:

BadFileException - If the file content has been modified.

IllegalArgumentException - If the data container is invalid.

IllegalStateException - If the cipher is in an inappropriate state.

CryptoSystemException - If a unknown error occurred.