Inheritance diagram for fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20:

Public Member Functions
	__construct (CipherEnum $cipher, ModeEnum $mode, PaddingInterface $padding, $key, $tagLength=self::DEFAULT_TAG_LENGTH)

	decrypt ($iv, $data, $tag=null, $aad= '')

	encrypt ($iv, $data, &$tag=null, $aad= '')

	getBlockSize ()

	getCipher ()

	getIVSize ()

	getKey ()

Protected Member Functions
	basicXcrypt ($plain, $iv, $counter=0)

	block ($iv, $counter)

Static Protected Member Functions
static	quarterRound (&$a, &$b, &$c, &$d)

Protected Attributes
	$cipher

	$key
	Secret key used to encrypt/decrypt data.

	$tagLength
	Tag length in bytes; 16 when AEAD is enabled, 0 otherwise.

Additional Inherited Members
Public Attributes inherited from fpoirotte\Cryptal\Implementers\CryptoInterface
const	DEFAULT_TAG_LENGTH = 16

Detailed Description

ChaCha20 block cipher, with optional AEAD (as per RFC 7539).

Note: When using AEAD, this class implements the construction defined in RFC 7539.

See also: http://cr.yp.to/chacha/chacha-20080128.pdf; https://tools.ietf.org/html/rfc7539

Definition at line 25 of file ChaCha20.php.

Constructor & Destructor Documentation

fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20::__construct	(	CipherEnum	$cipher,
		ModeEnum	$mode,
		PaddingInterface	$padding,
			$key,
			$tagLength = `self::DEFAULT_TAG_LENGTH`
	)

Construct a new encryption/decryption context.

Parameters

CipherEnum	$cipher	Cipher algorithm to use.
ModeEnum	$mode	Cryptography mode to apply to the cipher.
PaddingInterface	$padding	Padding scheme to use.
string	$key	Secret key used for encryption/decryption.
int	$tagLength	Length (in bytes) of the authentication tags to generate.

Note: The $tagLength parameter is unused unless the supplied mode supports Authenticated Encryption with Additional Data (AEAD).

Definition at line 35 of file ChaCha20.php.

fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20::decrypt	(	$iv,
		$data,
		$tag = `null`,
		$aad = `''`
	)

Decrypt some data.

Parameters

string	$iv	Initialization Vector for the operation.
string	$data	Data to decrypt.
string	$tag	Authentication tag.
string	$aad	Additional authenticated data.

Return values

string Plaintext (decrypted data).

Note: The $iv parameter is unused for some modes of operations (namely MODE_ECB). Still, this parameter is mandatory and an empty string may be passed for those modes.; An exception is thrown in case decryption fails, or the given authentication tag is incorrect (AEAD-only).; The $aad & $tag parameters are unused unless the required mode supports Authenticated Encryption with Additional Data (AEAD). MODE_GCM & MODE_EAX are known to support AEAD.

Definition at line 157 of file ChaCha20.php.

fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20::encrypt	(		$iv,
			$data,
		&	$tag = `null`,
			$aad = `''`
	)

Encrypt some data.

Parameters

string	$iv	Initialization Vector for the operation.
string	$data	Data to encrypt.
string	$tag	Variable where the generated tag will be stored.
string	$aad	Additional authenticated data.

Return values

string Ciphertext (encrypted data).

Note: The $iv parameter is unused for some modes of operations (namely MODE_ECB). Still, this parameter is mandatory and an empty string may be passed for those modes.; An exception is thrown in case encryption fails.; The $aad & $tag parameters are unused unless the required mode supports Authenticated Encryption with Additional Data (AEAD). MODE_GCM & MODE_EAX are known to support AEAD.

Definition at line 134 of file ChaCha20.php.

fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20::getBlockSize ( )

Get the block size, in bytes.

Return values