fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20Openssh Class Reference

Inheritance diagram for fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20Openssh:

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= '')
	getIVSize ()
Public Member Functions inherited from fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20
	__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 Attributes
	$cipher
	$header
	Header encryptor.
	$key
	$main
	Main encryptor.
Protected Attributes inherited from fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20
	$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
Protected Member Functions inherited from fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20
	basicXcrypt ($plain, $iv, $counter=0)
	block ($iv, $counter)
Static Protected Member Functions inherited from fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20
static	quarterRound (&$a, &$b, &$c, &$d)

Detailed Description

ChaCha20 block cipher with AEAD (OpenSSH variante).

Note

This class implements the AEAD construction defined in http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/PROTOCOL.chacha20poly1305.

See also

http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/usr.bin/ssh/PROTOCOL.chacha20poly1305

Definition at line 25 of file ChaCha20Openssh.php.

Constructor & Destructor Documentation

fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20Openssh::__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).

Implements fpoirotte\Cryptal\Implementers\CryptoInterface.

Definition at line 36 of file ChaCha20Openssh.php.

References fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20\$tagLength.

Member Function Documentation

fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20Openssh::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.

Implements fpoirotte\Cryptal\Implementers\CryptoInterface.

Definition at line 92 of file ChaCha20Openssh.php.

References fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20Openssh\getIVSize(), and fpoirotte\Cryptal\Implementers\AbstractMac\mac().

fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20Openssh::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.

Implements fpoirotte\Cryptal\Implementers\CryptoInterface.

Definition at line 69 of file ChaCha20Openssh.php.

References fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20Openssh\getIVSize(), and fpoirotte\Cryptal\Implementers\AbstractMac\mac().

fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20Openssh::getIVSize

(

)

Get the size of the Initialization Vector, in bytes.

Return values

int	Required size for the Initialization Vector. Might be zero in case the given cipher/mode combination does not require an initialization vector.

Implements fpoirotte\Cryptal\Implementers\CryptoInterface.

Definition at line 118 of file ChaCha20Openssh.php.

Referenced by fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20Openssh\decrypt(), and fpoirotte\Cryptal\DefaultAlgorithms\ChaCha20Openssh\encrypt().

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

• src/Cryptal/DefaultAlgorithms/ChaCha20Openssh.php