nn::crypto Namespace

The namespace of the encryption library.

Block Cipher API

Encryption using a block cipher has the following four stages, depending on the sophistication of the API.
If at all possible, use the first stage, wherein a single function performs all operations.

1. A single function that carries out all operations

   It includes functions such as EncryptAes128Ctr, DecryptAes128Ctr, EncryptAndGenerateAes128Ccm, and DecryptAndVerifyAes128Ccm.
   Perform all processing required to encrypt by calling only this one function and specifying the encryption key, data to encrypt, and buffer to store the results.

2. Batch processing using a combination of a block cipher and a cipher mode

   This uses an instance of a class derived from BlockCipher and one of the following functions.

   • The Encrypt function from the Encryptor derived class
   • The Decrypt function from the Decryptor derived class
   • The EncryptAndGenerate function from AuthenticatedEncryptor derived class
   • The DecryptAndVerify function from the AuthenticatedDecryptor derived class
   You cannot use instances of these classes. You can use any combination of block cipher and cipher mode. Enter all required parameters and run as a batch. Consequently, all targeted data must be loaded into memory.

3. Stream processing using a combination of a block cipher and a cipher mode

   Uses instances of a class derived from BlockCipher, and a class derived from CipherMode. You can use any combination of block cipher and cipher mode. You can process a little at a time this way, allowing you to process a large volume of data using a smaller buffer to load and process the data.

4. Directly using the block cipher

   Uses only an instance of a class derived from BlockCipher.
   Do not use this method unless you know enough about encryption, and have a firm understanding of what you are doing.

2011/10/27

Added explanation of the block cipher API.

2010/01/07

Initial version.