Commit 6f9bbc4b authored by Bong Cosca's avatar Bong Cosca
Browse files

Implement Bcrypt->needs_rehash()

parent ee989844

bcrypt.php

+18 −3
Original line number Diff line number Diff line
@@ -18,10 +18,14 @@ class Bcrypt extends Prefab { 


	//@{ Error messages

	const

		E_Cost='Invalid cost parameter',

		E_Salt='Invalid salt (must be at least 22 alphanumeric characters)';

		E_CostArg='Invalid cost parameter',

		E_SaltArg='Salt must be at least 22 alphanumeric characters';

	//@}



	//! Default cost

	const

		COST=10;



	/**

	*	Generate bcrypt hash of string

	*	@return string|FALSE
@@ -29,7 +33,7 @@ class Bcrypt extends Prefab { 
	*	@param $salt string

	*	@param $cost int

	**/

	function hash($pw,$salt=NULL,$cost=10) {

	function hash($pw,$salt=NULL,$cost=self::COST) {

		if ($cost<4 || $cost>31)

			trigger_error(self::E_Cost);

		$len=22;
@@ -54,6 +58,17 @@ class Bcrypt extends Prefab { 
		return strlen($hash)>13?$hash:FALSE;

	}



	/**

	*	Check if password is still strong enough

	*	@return bool

	*	@param $hash string

	*	@param $cost int

	**/

	function needs_rehash($hash,$cost=self::COST) {

		list($pwcost)=sscanf($hash,"$2y$%d$");

		return $pwcost!=$cost;

	}



	/**

	*	Verify password against hash using timing attack resistant approach

	*	@return bool