DiffieHellman Class Reference

PHP implementation of the Diffie-Hellman public key encryption algorithm. More...

Public Member Functions
	__construct ($prime, $generator, $privateKey=null, $privateKeyFormat=self::FORMAT_NUMBER)
	Constructor; if set construct the object using the parameter array to set values for Prime, Generator and Private.
	generateKeys ()
	Generate own public key.
	setPublicKey ($number, $format=self::FORMAT_NUMBER)
	Setter for the value of the public number.
	getPublicKey ($format=self::FORMAT_NUMBER)
	Returns own public key for communication to the second party to this transaction.
	computeSecretKey ($publicKey, $publicKeyFormat=self::FORMAT_NUMBER, $secretKeyFormat=self::FORMAT_NUMBER)
	Compute the shared secret key based on the public key received from the the second party to this transaction.
	getSharedSecretKey ($format=self::FORMAT_NUMBER)
	Return the computed shared secret key from the DiffieHellman transaction.
	setPrime ($number)
	Setter for the value of the prime number.
	getPrime ($format=self::FORMAT_NUMBER)
	Getter for the value of the prime number.
	setGenerator ($number)
	Setter for the value of the generator number.
	getGenerator ($format=self::FORMAT_NUMBER)
	Getter for the value of the generator number.
	setPrivateKey ($number, $format=self::FORMAT_NUMBER)
	Setter for the value of the private number.
	getPrivateKey ($format=self::FORMAT_NUMBER)
	Getter for the value of the private number.
	hasPrivateKey ()
	Check whether a private key currently exists.

Static Public Member Functions
static	useOpensslExtension ($flag=true)
	Set whether to use openssl extension.

Public Attributes
const	DEFAULT_KEY_SIZE = 2048
const	FORMAT_BINARY = 'binary'
	Key formats.
const	FORMAT_NUMBER = 'number'
const	FORMAT_BTWOC = 'btwoc'

Static Public Attributes
static	$useOpenssl = true

Protected Member Functions
	convert ($number, $inputFormat=self::FORMAT_NUMBER, $outputFormat=self::FORMAT_BINARY)
	Convert number between formats.
	generatePrivateKey ()
	In the event a private number/key has not been set by the user, or generated by ext/openssl, a best attempt will be made to generate a random key.

Protected Attributes
	$opensslKeyResource = null

Detailed Description

PHP implementation of the Diffie-Hellman public key encryption algorithm.

Allows two unassociated parties to establish a joint shared secret key to be used in encrypting subsequent communications.

Constructor & Destructor Documentation

__construct	(		$prime,
			$generator,
			$privateKey = null,
			$privateKeyFormat = self::FORMAT_NUMBER
	)

Constructor; if set construct the object using the parameter array to set values for Prime, Generator and Private.

If a Private Key is not set, one will be generated at random.

Parameters

string	$prime
string	$generator
string	$privateKey
string	$privateKeyFormat

Member Function Documentation

computeSecretKey	(		$publicKey,
			$publicKeyFormat = self::FORMAT_NUMBER,
			$secretKeyFormat = self::FORMAT_NUMBER
	)

Compute the shared secret key based on the public key received from the the second party to this transaction.

This should agree to the secret key the second party computes on our own public key. Once in agreement, the key is known to only to both parties. By default, the function expects the public key to be in binary form which is the typical format when being transmitted.

If you need the binary form of the shared secret key, call getSharedSecretKey() with the optional parameter for Binary output.

Parameters

string	$publicKey
string	$publicKeyFormat
string	$secretKeyFormat

Returns

string

Exceptions

\Zend\Crypt\Exception\InvalidArgumentException
\Zend\Crypt\Exception\RuntimeException

convert (   $number,   $inputFormat = self::FORMAT_NUMBER,   $outputFormat = self::FORMAT_BINARY  )

protected

Convert number between formats.

Parameters

string	$number
string	$inputFormat
string	$outputFormat

Returns

string

generateKeys

(

)

Generate own public key.

If a private number has not already been set, one will be generated at this stage.

Returns

DiffieHellman

Exceptions

\Zend\Crypt\Exception\RuntimeException

generatePrivateKey ( )

protected

In the event a private number/key has not been set by the user, or generated by ext/openssl, a best attempt will be made to generate a random key.

Having a random number generator installed on linux/bsd is highly recommended! The alternative is not recommended for production unless without any other option.

Returns

string

getGenerator

(

$format = self::FORMAT_NUMBER

)

Getter for the value of the generator number.

Parameters

string

$format

Returns

string

Exceptions

\Zend\Crypt\Exception\InvalidArgumentException

getPrime

(

$format = self::FORMAT_NUMBER

)

Getter for the value of the prime number.

Parameters

string

$format

Returns

string

Exceptions

\Zend\Crypt\Exception\InvalidArgumentException

getPrivateKey

(

$format = self::FORMAT_NUMBER

)

Getter for the value of the private number.

Parameters

string

$format

Returns

string

getPublicKey

(

$format = self::FORMAT_NUMBER

)

Returns own public key for communication to the second party to this transaction.

Parameters

string

$format

Returns

string

Exceptions

\Zend\Crypt\Exception\InvalidArgumentException

getSharedSecretKey

(

$format = self::FORMAT_NUMBER

)

Return the computed shared secret key from the DiffieHellman transaction.

Parameters

string

$format

Returns

string

Exceptions

\Zend\Crypt\Exception\InvalidArgumentException

hasPrivateKey

(

)

Check whether a private key currently exists.

Returns

bool

setGenerator

(

$number

)

Setter for the value of the generator number.

Parameters

string

$number

Returns

DiffieHellman

Exceptions

\Zend\Crypt\Exception\InvalidArgumentException

setPrime

(

$number

)

Setter for the value of the prime number.

Parameters

string

$number

Returns

DiffieHellman

Exceptions

\Zend\Crypt\Exception\InvalidArgumentException

setPrivateKey	(		$number,
			$format = self::FORMAT_NUMBER
	)

Setter for the value of the private number.

Parameters

string	$number
string	$format

Returns

DiffieHellman

Exceptions

\Zend\Crypt\Exception\InvalidArgumentException

setPublicKey	(		$number,
			$format = self::FORMAT_NUMBER
	)

Setter for the value of the public number.

Parameters

string	$number
string	$format

Returns

DiffieHellman

Exceptions

\Zend\Crypt\Exception\InvalidArgumentException

static useOpensslExtension (   $flag = true )

static

Set whether to use openssl extension.

Parameters

bool

$flag

Member Data Documentation

$opensslKeyResource = null

protected

$useOpenssl = true

static

const DEFAULT_KEY_SIZE = 2048

const FORMAT_BINARY = 'binary'

Key formats.

const FORMAT_BTWOC = 'btwoc'

const FORMAT_NUMBER = 'number'