Aes_ctr_cipher< TYPE > Class Template Reference

The class implements AES-CTR encryption/decryption. More...

#include <stream_cipher.h>

Inheritance diagram for Aes_ctr_cipher< TYPE >:

Public Member Functions
	~Aes_ctr_cipher () override
bool	open (const Key_string &password, int header_size) override
	Open the cipher with given password. More...
void	close () override
	Close the cipher. More...
bool	encrypt (unsigned char *dest, const unsigned char *src, int length) override
	Encrypt data. More...
bool	decrypt (unsigned char *dest, const unsigned char *src, int length) override
	Decrypt data. More...
bool	set_stream_offset (uint64_t offset) override
	Support encrypting/decrypting data at random position of a stream. More...
Public Member Functions inherited from Stream_cipher
virtual	~Stream_cipher ()=default
int	get_header_size ()
	Returns the size of the header of the stream being encrypted/decrypted. More...

Static Public Attributes
static const int	PASSWORD_LENGTH = Aes_ctr::PASSWORD_LENGTH
static const int	AES_BLOCK_SIZE = Aes_ctr::AES_BLOCK_SIZE
static const int	FILE_KEY_LENGTH = Aes_ctr::FILE_KEY_LENGTH

Private Member Functions
bool	init_cipher (uint64_t offset)
	Initialize OpenSSL cipher related context and IV. More...
void	deinit_cipher ()
	Destroy OpenSSL cipher related context. More...

Private Attributes
EVP_CIPHER_CTX *	m_ctx = nullptr
unsigned char	m_file_key [FILE_KEY_LENGTH]
unsigned char	m_iv [AES_BLOCK_SIZE]

Additional Inherited Members
Protected Attributes inherited from Stream_cipher
int	m_header_size = 0

Detailed Description

template<Cipher_type TYPE>
class Aes_ctr_cipher< TYPE >

The class implements AES-CTR encryption/decryption.

It supports to encrypt/decrypt a stream in both sequential and random way.

Constructor & Destructor Documentation

~Aes_ctr_cipher()

template<Cipher_type TYPE>

Aes_ctr_cipher< TYPE >::~Aes_ctr_cipher< TYPE >

override

Member Function Documentation

close()

template<Cipher_type TYPE>

void Aes_ctr_cipher< TYPE >::close ( )

overridevirtual

Close the cipher.

Implements Stream_cipher.

decrypt()

template<Cipher_type TYPE>

bool Aes_ctr_cipher< TYPE >::decrypt ( unsigned char *  dest, const unsigned char *  src, int  length  )

overridevirtual

Decrypt data.

Parameters

[in]	dest	The buffer for storing decrypted data. It should be at least 'length' bytes.
[in]	src	The data which will be decrypted.
[in]	length	Length of the data.

Return values

false	Success.
true	Error.

Implements Stream_cipher.

deinit_cipher()

template<Cipher_type TYPE>

void Aes_ctr_cipher< TYPE >::deinit_cipher

private

Destroy OpenSSL cipher related context.

encrypt()

template<Cipher_type TYPE>

bool Aes_ctr_cipher< TYPE >::encrypt ( unsigned char *  dest, const unsigned char *  src, int  length  )

overridevirtual

Encrypt data.

Parameters

[in]	dest	The buffer for storing encrypted data. It should be at least 'length' bytes.
[in]	src	The data which will be encrypted.
[in]	length	Length of the data.

Return values

false	Success.
true	Error.

Implements Stream_cipher.

init_cipher()

template<Cipher_type TYPE>

bool Aes_ctr_cipher< TYPE >::init_cipher ( uint64_t  offset )

private

Initialize OpenSSL cipher related context and IV.

Parameters

[in]

offset

The stream offset to compute the AES-CTR counter which will be set into IV.

Return values

false	Success.
true	Error.

open()

template<Cipher_type TYPE>

bool Aes_ctr_cipher< TYPE >::open ( const Key_string &  password, int  header_size  )

overridevirtual

Open the cipher with given password.

Parameters

[in]	password	The password which is used to initialize the cipher.
[in]	header_size	The encrypted stream offset wrt the down stream.

Return values

false	Success.
true	Error.

Implements Stream_cipher.

set_stream_offset()

template<Cipher_type TYPE>

bool Aes_ctr_cipher< TYPE >::set_stream_offset ( uint64_t  offset )

overridevirtual

Support encrypting/decrypting data at random position of a stream.

Parameters

[in]

offset

The stream offset of the data which will be encrypted/ decrypted in next encrypt()/decrypt() call.

Return values

false	Success.
true	Error.

Implements Stream_cipher.

Member Data Documentation

AES_BLOCK_SIZE

template<Cipher_type TYPE>

const int Aes_ctr_cipher< TYPE >::AES_BLOCK_SIZE = Aes_ctr::AES_BLOCK_SIZE

static

FILE_KEY_LENGTH

template<Cipher_type TYPE>

const int Aes_ctr_cipher< TYPE >::FILE_KEY_LENGTH = Aes_ctr::FILE_KEY_LENGTH

static

m_ctx

template<Cipher_type TYPE>

EVP_CIPHER_CTX* Aes_ctr_cipher< TYPE >::m_ctx = nullptr

private

m_file_key

template<Cipher_type TYPE>

unsigned char Aes_ctr_cipher< TYPE >::m_file_key[FILE_KEY_LENGTH]

private

m_iv

template<Cipher_type TYPE>

unsigned char Aes_ctr_cipher< TYPE >::m_iv[AES_BLOCK_SIZE]

private

PASSWORD_LENGTH

template<Cipher_type TYPE>

const int Aes_ctr_cipher< TYPE >::PASSWORD_LENGTH = Aes_ctr::PASSWORD_LENGTH

static

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The documentation for this class was generated from the following files:

• sql/stream_cipher.h
• sql/stream_cipher.cc