silverstripe-framework/Security/Permission.php
2016-07-11 23:45:41 +01:00

737 lines
20 KiB
PHP

<?php
namespace SilverStripe\Security;
use SilverStripe\ORM\DB;
use SilverStripe\ORM\DataObject;
use SilverStripe\ORM\ArrayList;
use SilverStripe\ORM\SS_List;
use TemplateGlobalProvider;
use ClassInfo;
use TestOnly;
/**
* Represents a permission assigned to a group.
* @package framework
* @subpackage security
*
* @property string Code
* @property int Arg
* @property int Type
*
* @property int GroupID
*
* @method Group Group()
*/
class Permission extends DataObject implements TemplateGlobalProvider {
// the (1) after Type specifies the DB default value which is needed for
// upgrades from older SilverStripe versions
private static $db = array(
"Code" => "Varchar(255)",
"Arg" => "Int",
"Type" => "Int(1)"
);
private static $has_one = array(
"Group" => "SilverStripe\\Security\\Group"
);
private static $indexes = array(
"Code" => true
);
private static $defaults = array(
"Type" => 1
);
private static $table_name = "Permission";
/**
* This is the value to use for the "Type" field if a permission should be
* granted.
*/
const GRANT_PERMISSION = 1;
/**
* This is the value to use for the "Type" field if a permission should be
* denied.
*/
const DENY_PERMISSION = -1;
/**
* This is the value to use for the "Type" field if a permission should be
* inherited.
*/
const INHERIT_PERMISSION = 0;
/**
* Method to globally disable "strict" checking, which means a permission
* will be granted if the key does not exist at all.
*
* @var array
*/
private static $declared_permissions = null;
/**
* Linear list of declared permissions in the system.
*
* @var array
*/
private static $declared_permissions_list = null;
/**
* @config
* @var $strict_checking Boolean Method to globally disable "strict" checking,
* which means a permission will be granted if the key does not exist at all.
*/
private static $strict_checking = true;
/**
* Set to false to prevent the 'ADMIN' permission from implying all
* permissions in the system
*
* @config
* @var bool
*/
private static $admin_implies_all = true;
/**
* a list of permission codes which doesn't appear in the Permission list
* when make the {@link PermissionCheckboxSetField}
* @config
* @var array;
*/
private static $hidden_permissions = array();
/**
* @config These permissions can only be applied by ADMIN users, to prevent
* privilege escalation on group assignments and inheritance.
* @var array
*/
private static $privileged_permissions = array(
'ADMIN',
'APPLY_ROLES',
'EDIT_PERMISSIONS'
);
/**
* Check that the current member has the given permission.
*
* @param string|array $code Code of the permission to check (case-sensitive)
* @param string $arg Optional argument (e.g. a permissions for a specific page)
* @param int|Member $member Optional member instance or ID. If set to NULL, the permssion
* will be checked for the current user
* @param bool $strict Use "strict" checking (which means a permission
* will be granted if the key does not exist at all)?
* @return int|bool The ID of the permission record if the permission
* exists; FALSE otherwise. If "strict" checking is
* disabled, TRUE will be returned if the permission does not exist at all.
*/
public static function check($code, $arg = "any", $member = null, $strict = true) {
if(!$member) {
if(!Member::currentUserID()) {
return false;
}
$member = Member::currentUserID();
}
return self::checkMember($member, $code, $arg, $strict);
}
/**
* Permissions cache. The format is a map, where the keys are member IDs, and the values are
* arrays of permission codes.
*/
private static $cache_permissions = array();
/**
* Flush the permission cache, for example if you have edited group membership or a permission record.
* @todo Call this whenever Group_Members is added to or removed from
*/
public static function flush_permission_cache() {
self::$cache_permissions = array();
}
/**
* Check that the given member has the given permission.
*
* @param int|Member memberID The ID of the member to check. Leave blank for the current member.
* Alternatively you can use a member object.
* @param string|array $code Code of the permission to check (case-sensitive)
* @param string $arg Optional argument (e.g. a permissions for a specific page)
* @param bool $strict Use "strict" checking (which means a permission
* will be granted if the key does not exist at all)?
* @return int|bool The ID of the permission record if the permission
* exists; FALSE otherwise. If "strict" checking is
* disabled, TRUE will be returned if the permission does not exist at all.
*/
public static function checkMember($member, $code, $arg = "any", $strict = true) {
if(!$member) {
$memberID = $member = Member::currentUserID();
} else {
$memberID = (is_object($member)) ? $member->ID : $member;
}
if (!$memberID) {
return false;
}
// Turn the code into an array as we may need to add other permsissions to the set we check
if(!is_array($code)) {
$code = array($code);
}
// Check if admin should be treated as holding all permissions
$adminImpliesAll = (bool)static::config()->admin_implies_all;
if($arg == 'any') {
// Cache the permissions in memory
if(!isset(self::$cache_permissions[$memberID])) {
self::$cache_permissions[$memberID] = self::permissions_for_member($memberID);
}
foreach ($code as $permCode) {
if ($permCode === 'CMS_ACCESS') {
foreach (self::$cache_permissions[$memberID] as $perm) {
//if they have admin rights OR they have an explicit access to the CMS then give permission
if (($adminImpliesAll && $perm == 'ADMIN') || substr($perm, 0, 11) === 'CMS_ACCESS_') {
return true;
}
}
}
elseif (substr($permCode, 0, 11) === 'CMS_ACCESS_' && !in_array('CMS_ACCESS_LeftAndMain', $code)) {
//cms_access_leftandmain means access to all CMS areas
$code[] = 'CMS_ACCESS_LeftAndMain';
}
}
// if ADMIN has all privileges, then we need to push that code in
if($adminImpliesAll) {
$code[] = "ADMIN";
}
// Multiple $code values - return true if at least one matches, ie, intersection exists
return (bool)array_intersect($code, self::$cache_permissions[$memberID]);
}
// Code filters
$codeParams = is_array($code) ? $code : array($code);
$codeClause = DB::placeholders($codeParams);
$adminParams = $adminImpliesAll ? array('ADMIN') : array();
$adminClause = $adminImpliesAll ? ", ?" : '';
// The following code should only be used if you're not using the "any" arg. This is kind
// of obselete functionality and could possibly be deprecated.
$groupParams = self::groupList($memberID);
if(empty($groupParams)) return false;
$groupClause = DB::placeholders($groupParams);
// Arg component
$argClause = "";
$argParams = array();
switch($arg) {
case "any":
break;
case "all":
$argClause = " AND \"Arg\" = ?";
$argParams = array(-1);
break;
default:
if(is_numeric($arg)) {
$argClause = "AND \"Arg\" IN (?, ?) ";
$argParams = array(-1, $arg);
} else {
user_error("Permission::checkMember: bad arg '$arg'", E_USER_ERROR);
}
}
// Raw SQL for efficiency
$permission = DB::prepared_query(
"SELECT \"ID\"
FROM \"Permission\"
WHERE (
\"Code\" IN ($codeClause $adminClause)
AND \"Type\" = ?
AND \"GroupID\" IN ($groupClause)
$argClause
)",
array_merge(
$codeParams,
$adminParams,
array(self::GRANT_PERMISSION),
$groupParams,
$argParams
)
)->value();
if($permission) return $permission;
// Strict checking disabled?
if(!static::config()->strict_checking || !$strict) {
$hasPermission = DB::prepared_query(
"SELECT COUNT(*)
FROM \"Permission\"
WHERE (
\"Code\" IN ($codeClause) AND
\"Type\" = ?
)",
array_merge($codeParams, array(self::GRANT_PERMISSION))
)->value();
if(!$hasPermission) return false;
}
return false;
}
/**
* Get all the 'any' permission codes available to the given member.
*
* @param int $memberID
* @return array
*/
public static function permissions_for_member($memberID) {
$groupList = self::groupList($memberID);
if($groupList) {
$groupCSV = implode(", ", $groupList);
$allowed = array_unique(DB::query("
SELECT \"Code\"
FROM \"Permission\"
WHERE \"Type\" = " . self::GRANT_PERMISSION . " AND \"GroupID\" IN ($groupCSV)
UNION
SELECT \"Code\"
FROM \"PermissionRoleCode\" PRC
INNER JOIN \"PermissionRole\" PR ON PRC.\"RoleID\" = PR.\"ID\"
INNER JOIN \"Group_Roles\" GR ON GR.\"PermissionRoleID\" = PR.\"ID\"
WHERE \"GroupID\" IN ($groupCSV)
")->column());
$denied = array_unique(DB::query("
SELECT \"Code\"
FROM \"Permission\"
WHERE \"Type\" = " . self::DENY_PERMISSION . " AND \"GroupID\" IN ($groupCSV)
")->column());
return array_diff($allowed, $denied);
}
return array();
}
/**
* Get the list of groups that the given member belongs to.
*
* Call without an argument to get the groups that the current member
* belongs to. In this case, the results will be session-cached.
*
* @param int $memberID The ID of the member. Leave blank for the current
* member.
* @return array Returns a list of group IDs to which the member belongs
* to or NULL.
*/
public static function groupList($memberID = null) {
// Default to current member, with session-caching
if(!$memberID) {
$member = Member::currentUser();
if($member && isset($_SESSION['Permission_groupList'][$member->ID]))
return $_SESSION['Permission_groupList'][$member->ID];
} else {
$member = DataObject::get_by_id("SilverStripe\\Security\\Member", $memberID);
}
if($member) {
// Build a list of the IDs of the groups. Most of the heavy lifting
// is done by Member::Groups
// NOTE: This isn't effecient; but it's called once per session so
// it's a low priority to fix.
$groups = $member->Groups();
$groupList = array();
if($groups) {
foreach($groups as $group)
$groupList[] = $group->ID;
}
// Session caching
if(!$memberID) {
$_SESSION['Permission_groupList'][$member->ID] = $groupList;
}
return isset($groupList) ? $groupList : null;
}
}
/**
* Grant the given permission code/arg to the given group
*
* @param int $groupID The ID of the group
* @param string $code The permission code
* @param string $arg Optional: The permission argument (e.g. a page ID).
* @returns Permission Returns the new permission object.
*/
public static function grant($groupID, $code, $arg = "any") {
$perm = new Permission();
$perm->GroupID = $groupID;
$perm->Code = $code;
$perm->Type = self::GRANT_PERMISSION;
// Arg component
switch($arg) {
case "any":
break;
case "all":
$perm->Arg = -1;
break;
default:
if(is_numeric($arg)) {
$perm->Arg = $arg;
} else {
user_error("Permission::checkMember: bad arg '$arg'",
E_USER_ERROR);
}
}
$perm->write();
return $perm;
}
/**
* Deny the given permission code/arg to the given group
*
* @param int $groupID The ID of the group
* @param string $code The permission code
* @param string $arg Optional: The permission argument (e.g. a page ID).
* @returns Permission Returns the new permission object.
*/
public static function deny($groupID, $code, $arg = "any") {
$perm = new Permission();
$perm->GroupID = $groupID;
$perm->Code = $code;
$perm->Type = self::DENY_PERMISSION;
// Arg component
switch($arg) {
case "any":
break;
case "all":
$perm->Arg = -1;
break;
default:
if(is_numeric($arg)) {
$perm->Arg = $arg;
} else {
user_error("Permission::checkMember: bad arg '$arg'",
E_USER_ERROR);
}
}
$perm->write();
return $perm;
}
/**
* Returns all members for a specific permission.
*
* @param $code String|array Either a single permission code, or a list of permission codes
* @return SS_List Returns a set of member that have the specified
* permission.
*/
public static function get_members_by_permission($code) {
$toplevelGroups = self::get_groups_by_permission($code);
if (!$toplevelGroups) return new ArrayList();
$groupIDs = array();
foreach($toplevelGroups as $group) {
$familyIDs = $group->collateFamilyIDs();
if(is_array($familyIDs)) {
$groupIDs = array_merge($groupIDs, array_values($familyIDs));
}
}
if(empty($groupIDs)) return new ArrayList();
$groupClause = DB::placeholders($groupIDs);
/** @skipUpgrade */
$members = Member::get()
->where(array("\"Group\".\"ID\" IN ($groupClause)" => $groupIDs))
->leftJoin("Group_Members", '"Member"."ID" = "Group_Members"."MemberID"')
->leftJoin("Group", '"Group_Members"."GroupID" = "Group"."ID"');
return $members;
}
/**
* Return all of the groups that have one of the given permission codes
* @param array|string $codes Either a single permission code, or an array of permission codes
* @return SS_List The matching group objects
*/
public static function get_groups_by_permission($codes) {
$codeParams = is_array($codes) ? $codes : array($codes);
$codeClause = DB::placeholders($codeParams);
// Via Roles are groups that have the permission via a role
/** @skipUpgrade */
return Group::get()
->where(array(
"\"PermissionRoleCode\".\"Code\" IN ($codeClause) OR \"Permission\".\"Code\" IN ($codeClause)"
=> array_merge($codeParams, $codeParams)
))
->leftJoin('Permission', "\"Permission\".\"GroupID\" = \"Group\".\"ID\"")
->leftJoin('Group_Roles', "\"Group_Roles\".\"GroupID\" = \"Group\".\"ID\"")
->leftJoin('PermissionRole', "\"Group_Roles\".\"PermissionRoleID\" = \"PermissionRole\".\"ID\"")
->leftJoin('PermissionRoleCode', "\"PermissionRoleCode\".\"RoleID\" = \"PermissionRole\".\"ID\"");
}
/**
* Get a list of all available permission codes, both defined through the
* {@link PermissionProvider} interface, and all not explicitly defined codes existing
* as a {@link Permission} database record. By default, the results are
* grouped as denoted by {@link Permission_Group}.
*
* @param bool $grouped Group results into an array of permission groups.
* @return array Returns an array of all available permission codes. The
* array indicies are the permission codes as used in
* {@link Permission::check()}. The value is a description
* suitable for using in an interface.
*/
public static function get_codes($grouped = true) {
$classes = ClassInfo::implementorsOf('SilverStripe\\Security\\PermissionProvider');
$allCodes = array();
$adminCategory = _t('Permission.AdminGroup', 'Administrator');
$allCodes[$adminCategory]['ADMIN'] = array(
'name' => _t('Permission.FULLADMINRIGHTS', 'Full administrative rights'),
'help' => _t(
'Permission.FULLADMINRIGHTS_HELP',
'Implies and overrules all other assigned permissions.'
),
'sort' => 100000
);
if($classes) foreach($classes as $class) {
$SNG = singleton($class);
if($SNG instanceof TestOnly) continue;
$someCodes = $SNG->providePermissions();
if($someCodes) {
foreach($someCodes as $k => $v) {
if (is_array($v)) {
// There must be a category and name key.
if (!isset($v['category'])) user_error("The permission $k must have a category key",
E_USER_WARNING);
if (!isset($v['name'])) user_error("The permission $k must have a name key",
E_USER_WARNING);
if (!isset($allCodes[$v['category']])) $allCodes[$v['category']] = array();
$allCodes[$v['category']][$k] = array(
'name' => $v['name'],
'help' => isset($v['help']) ? $v['help'] : null,
'sort' => isset($v['sort']) ? $v['sort'] : 0
);
} else {
$allCodes['Other'][$k] = array(
'name' => $v,
'help' => null,
'sort' => 0
);
}
}
}
}
$flatCodeArray = array();
foreach($allCodes as $category) foreach($category as $code => $permission) $flatCodeArray[] = $code;
$otherPerms = DB::query("SELECT DISTINCT \"Code\" From \"Permission\" WHERE \"Code\" != ''")->column();
if($otherPerms) foreach($otherPerms as $otherPerm) {
if(!in_array($otherPerm, $flatCodeArray))
$allCodes['Other'][$otherPerm] = array(
'name' => $otherPerm,
'help' => null,
'sort' => 0
);
}
// Don't let people hijack ADMIN rights
if(!Permission::check("ADMIN")) unset($allCodes['ADMIN']);
ksort($allCodes);
$returnCodes = array();
foreach($allCodes as $category => $permissions) {
if($grouped) {
uasort($permissions, array(__CLASS__, 'sort_permissions'));
$returnCodes[$category] = $permissions;
} else {
$returnCodes = array_merge($returnCodes, $permissions);
}
}
return $returnCodes;
}
/**
* Sort permissions based on their sort value, or name
*
* @param array $a
* @param array $b
* @return int
*/
public static function sort_permissions($a, $b) {
if ($a['sort'] == $b['sort']) {
// Same sort value, do alpha instead
return strcmp($a['name'], $b['name']);
} else {
// Just numeric.
return $a['sort'] < $b['sort'] ? -1 : 1;
}
}
/**
* Get a linear list of the permissions in the system.
*
* @return array Linear list of declared permissions in the system.
*/
public static function get_declared_permissions_list() {
if(!self::$declared_permissions)
return null;
if(self::$declared_permissions_list)
return self::$declared_permissions_list;
self::$declared_permissions_list = array();
self::traverse_declared_permissions(self::$declared_permissions, self::$declared_permissions_list);
return self::$declared_permissions_list;
}
/**
* Look up the human-readable title for the permission as defined by <code>Permission::declare_permissions</code>
*
* @param string $perm Permission code
* @return string Label for the given permission, or the permission itself if the label doesn't exist
*/
public static function get_label_for_permission($perm) {
$list = self::get_declared_permissions_list();
if(array_key_exists($perm, $list)) return $list[$perm];
return $perm;
}
/**
* Recursively traverse the nested list of declared permissions and create
* a linear list.
*
* @param array $declared Nested structure of permissions.
* @param array $list List of permissions in the structure. The result will be
* written to this array.
*/
protected static function traverse_declared_permissions($declared, &$list) {
if(!is_array($declared))
return;
foreach($declared as $perm => $value) {
if($value instanceof Permission_Group) {
$list[] = $value->getName();
self::traverse_declared_permissions($value->getPermissions(), $list);
} else {
$list[$perm] = $value;
}
}
}
public function onBeforeWrite() {
parent::onBeforeWrite();
// Just in case we've altered someone's permissions
Permission::flush_permission_cache();
}
public static function get_template_global_variables() {
return array(
'HasPerm' => 'check'
);
}
}
/**
* Permission_Group class
*
* This class is used to group permissions together for showing on an
* interface.
* @package framework
* @subpackage security
*/
class Permission_Group {
/**
* Name of the permission group (can be used as label in an interface)
* @var string
*/
protected $name;
/**
* Associative array of permissions in this permission group. The array
* indicies are the permission codes as used in
* {@link Permission::check()}. The value is suitable for using in an
* interface.
* @var string
*/
protected $permissions = array();
/**
* Constructor
*
* @param string $name Text that could be used as label used in an
* interface
* @param array $permissions Associative array of permissions in this
* permission group. The array indicies are the
* permission codes as used in
* {@link Permission::check()}. The value is
* suitable for using in an interface.
*/
public function __construct($name, $permissions) {
$this->name = $name;
$this->permissions = $permissions;
}
/**
* Get the name of the permission group
*
* @return string Name (label) of the permission group
*/
public function getName() {
return $this->name;
}
/**
* Get permissions
*
* @return array Associative array of permissions in this permission
* group. The array indicies are the permission codes as
* used in {@link Permission::check()}. The value is
* suitable for using in an interface.
*/
public function getPermissions() {
return $this->permissions;
}
}