includes/password/UserPasswordPolicy.php
<?php
/**
* Password policy checking for a user
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
*/
use MediaWiki\HookContainer\HookRunner;
use MediaWiki\MediaWikiServices;
use MediaWiki\Status\Status;
use MediaWiki\User\UserIdentity;
/**
* Check if a user's password complies with any password policies that apply to that
* user, based on the user's group membership.
* @since 1.26
*/
class UserPasswordPolicy {
/**
* @var array[]
*/
private $policies;
/**
* Mapping of statements to the function that will test the password for compliance. The
* checking functions take the policy value, the user, and password, and return a Status
* object indicating compliance.
* @var callable[]
*/
private $policyCheckFunctions;
/**
* @param array[] $policies List of lists of policies per user group
* @param callable[] $checks mapping statement to its checking function. Checking functions are
* called with the policy value for this user, the user object, and the password to check.
*/
public function __construct( array $policies, array $checks ) {
if ( !isset( $policies['default'] ) ) {
throw new InvalidArgumentException(
'Must include a \'default\' password policy'
);
}
$this->policies = $policies;
foreach ( $checks as $statement => $check ) {
if ( !is_callable( $check ) ) {
throw new InvalidArgumentException(
"Policy check functions must be callable. '$statement' isn't callable."
);
}
$this->policyCheckFunctions[$statement] = $check;
}
}
/**
* Check if a password meets the effective password policy for a User.
* @param UserIdentity $user whose policy we are checking
* @param string $password the password to check
* @return Status error to indicate the password didn't meet the policy, or fatal to
* indicate the user shouldn't be allowed to login. The status value will be an array,
* potentially with the following keys:
* - forceChange: do not allow the user to login without changing the password if invalid.
* - suggestChangeOnLogin: prompt for a password change on login if the password is invalid.
*/
public function checkUserPassword( UserIdentity $user, $password ) {
$effectivePolicy = $this->getPoliciesForUser( $user );
return $this->checkPolicies(
$user,
$password,
$effectivePolicy,
$this->policyCheckFunctions
);
}
/**
* Check if a password meets the effective password policy for a User, using a set
* of groups they may or may not belong to. This function does not use the DB, so can
* be used in the installer.
* @param UserIdentity $user whose policy we are checking
* @param string $password the password to check
* @param string[] $groups list of groups to which we assume the user belongs
* @return Status error to indicate the password didn't meet the policy, or fatal to
* indicate the user shouldn't be allowed to login. The status value will be an array,
* potentially with the following keys:
* - forceChange: do not allow the user to login without changing the password if invalid.
* - suggestChangeOnLogin: prompt for a password change on login if the password is invalid.
*/
public function checkUserPasswordForGroups( UserIdentity $user, $password, array $groups ) {
$effectivePolicy = self::getPoliciesForGroups(
$this->policies,
$groups,
$this->policies['default']
);
return $this->checkPolicies(
$user,
$password,
$effectivePolicy,
$this->policyCheckFunctions
);
}
/**
* @param UserIdentity $user
* @param string $password
* @param array $policies List of policy statements for the group the user belongs to
* @param callable[] $policyCheckFunctions
* @return Status
*/
private function checkPolicies( UserIdentity $user, $password, $policies, $policyCheckFunctions ) {
$status = Status::newGood( [] );
$forceChange = false;
$suggestChangeOnLogin = false;
$legacyUser = MediaWikiServices::getInstance()
->getUserFactory()
->newFromUserIdentity( $user );
foreach ( $policies as $policy => $settings ) {
if ( !isset( $policyCheckFunctions[$policy] ) ) {
throw new DomainException( "Invalid password policy config. No check defined for '$policy'." );
}
if ( !is_array( $settings ) ) {
// legacy format
$settings = [ 'value' => $settings ];
}
if ( !array_key_exists( 'value', $settings ) ) {
throw new DomainException( "Invalid password policy config. No value defined for '$policy'." );
}
$value = $settings['value'];
/** @var StatusValue $policyStatus */
$policyStatus = call_user_func(
$policyCheckFunctions[$policy],
$value,
$legacyUser,
$password
);
if ( !$policyStatus->isGood() ) {
if ( !empty( $settings['forceChange'] ) ) {
$forceChange = true;
}
if ( !empty( $settings['suggestChangeOnLogin'] ) ) {
$suggestChangeOnLogin = true;
}
}
$status->merge( $policyStatus );
}
if ( $status->isOK() ) {
if ( $forceChange ) {
$status->value['forceChange'] = true;
} elseif ( $suggestChangeOnLogin ) {
$status->value['suggestChangeOnLogin'] = true;
}
}
return $status;
}
/**
* Get the policy for a user, based on their group membership. Public so
* UI elements can access and inform the user.
* @param UserIdentity $user
* @return array the effective policy for $user
*/
public function getPoliciesForUser( UserIdentity $user ) {
$services = MediaWikiServices::getInstance();
$effectivePolicy = self::getPoliciesForGroups(
$this->policies,
$services->getUserGroupManager()
->getUserEffectiveGroups( $user ),
$this->policies['default']
);
$legacyUser = $services->getUserFactory()
->newFromUserIdentity( $user );
( new HookRunner( $services->getHookContainer() ) )->onPasswordPoliciesForUser( $legacyUser, $effectivePolicy );
return $effectivePolicy;
}
/**
* Utility function to get the effective policy from a list of policies, based
* on a list of groups.
* @param array[] $policies List of lists of policies per user group
* @param string[] $userGroups the groups from which we calculate the effective policy
* @param array $defaultPolicy the default policy to start from
* @return array effective policy
*/
public static function getPoliciesForGroups( array $policies, array $userGroups,
array $defaultPolicy
) {
$effectivePolicy = $defaultPolicy;
foreach ( $policies as $group => $policy ) {
if ( in_array( $group, $userGroups ) ) {
$effectivePolicy = self::maxOfPolicies(
$effectivePolicy,
$policy
);
}
}
return $effectivePolicy;
}
/**
* Utility function to get a policy that is the most restrictive of $p1 and $p2. For
* simplicity, we setup the policy values so the maximum value is always more restrictive.
* It is also used recursively to merge settings within the same policy.
* @param array $p1
* @param array $p2
* @return array containing the more restrictive values of $p1 and $p2
*/
public static function maxOfPolicies( array $p1, array $p2 ) {
$ret = [];
$keys = array_merge( array_keys( $p1 ), array_keys( $p2 ) );
foreach ( $keys as $key ) {
if ( !isset( $p1[$key] ) ) {
$ret[$key] = $p2[$key];
} elseif ( !isset( $p2[$key] ) ) {
$ret[$key] = $p1[$key];
} elseif ( !is_array( $p1[$key] ) && !is_array( $p2[$key] ) ) {
$ret[$key] = max( $p1[$key], $p2[$key] );
} else {
if ( !is_array( $p1[$key] ) ) {
$p1[$key] = [ 'value' => $p1[$key] ];
} elseif ( !is_array( $p2[$key] ) ) {
$p2[$key] = [ 'value' => $p2[$key] ];
}
$ret[$key] = self::maxOfPolicies( $p1[$key], $p2[$key] );
}
}
return $ret;
}
}