Fix LDAP race conditions

* getFromCache is wrapped in isCached
* inbetween the two calls the cache entry hits it's TTL
* getFromCache returns null
* this fix only checkes if the returned value is null and
  return only non-null values
This commit is contained in:
Morris Jobke 2016-04-18 10:32:15 +02:00
parent 85d809c0d3
commit 62a59854f0
No known key found for this signature in database
GPG key ID: 9CE5ED29E7FCD38A
6 changed files with 32 additions and 48 deletions

View file

@ -72,8 +72,9 @@ class GROUP_LDAP extends BackendUtility implements \OCP\GroupInterface {
return false;
}
$cacheKey = 'inGroup'.$uid.':'.$gid;
if($this->access->connection->isCached($cacheKey)) {
return $this->access->connection->getFromCache($cacheKey);
$inGroup = $this->access->connection->getFromCache($cacheKey);
if(!is_null($inGroup)) {
return (bool)$inGroup;
}
$userDN = $this->access->username2dn($uid);
@ -84,8 +85,8 @@ class GROUP_LDAP extends BackendUtility implements \OCP\GroupInterface {
}
$cacheKeyMembers = 'inGroup-members:'.$gid;
if($this->access->connection->isCached($cacheKeyMembers)) {
$members = $this->access->connection->getFromCache($cacheKeyMembers);
if(!is_null($members)) {
$this->cachedGroupMembers[$gid] = $members;
$isInGroup = in_array($userDN, $members);
$this->access->connection->writeToCache($cacheKey, $isInGroup);
@ -204,8 +205,9 @@ class GROUP_LDAP extends BackendUtility implements \OCP\GroupInterface {
}
// used extensively in cron job, caching makes sense for nested groups
$cacheKey = '_groupMembers'.$dnGroup;
if($this->access->connection->isCached($cacheKey)) {
return $this->access->connection->getFromCache($cacheKey);
$groupMembers = $this->access->connection->getFromCache($cacheKey);
if(!is_null($groupMembers)) {
return $groupMembers;
}
$seen[$dnGroup] = 1;
$members = $this->access->readAttribute($dnGroup, $this->access->connection->ldapGroupMemberAssocAttr,
@ -267,12 +269,10 @@ class GROUP_LDAP extends BackendUtility implements \OCP\GroupInterface {
*/
public function primaryGroupID2Name($gid, $dn) {
$cacheKey = 'primaryGroupIDtoName';
if($this->access->connection->isCached($cacheKey)) {
$groupNames = $this->access->connection->getFromCache($cacheKey);
if(isset($groupNames[$gid])) {
if(!is_null($groupNames) && isset($groupNames[$gid])) {
return $groupNames[$gid];
}
}
$domainObjectSid = $this->access->getSID($dn);
if($domainObjectSid === false) {
@ -440,8 +440,9 @@ class GROUP_LDAP extends BackendUtility implements \OCP\GroupInterface {
return array();
}
$cacheKey = 'getUserGroups'.$uid;
if($this->access->connection->isCached($cacheKey)) {
return $this->access->connection->getFromCache($cacheKey);
$userGroups = $this->access->connection->getFromCache($cacheKey);
if(!is_null($userGroups)) {
return $userGroups;
}
$userDN = $this->access->username2dn($uid);
if(!$userDN) {
@ -861,8 +862,9 @@ class GROUP_LDAP extends BackendUtility implements \OCP\GroupInterface {
* @return bool
*/
public function groupExists($gid) {
if($this->access->connection->isCached('groupExists'.$gid)) {
return $this->access->connection->getFromCache('groupExists'.$gid);
$groupExists = $this->access->connection->getFromCache('groupExists'.$gid);
if(!is_null($groupExists)) {
return (bool)$groupExists;
}
//getting dn, if false the group does not exist. If dn, it may be mapped

View file

@ -364,8 +364,9 @@ class Access extends LDAPUtility implements user\IUserTools {
$validGroupDNs = [];
foreach($groupDNs as $dn) {
$cacheKey = 'groupsMatchFilter-'.$dn;
if($this->connection->isCached($cacheKey)) {
if($this->connection->getFromCache($cacheKey)) {
$groupMatchFilter = $this->connection->getFromCache($cacheKey);
if(!is_null($groupMatchFilter)) {
if($groupMatchFilter) {
$validGroupDNs[] = $dn;
}
continue;
@ -1505,8 +1506,9 @@ class Access extends LDAPUtility implements user\IUserTools {
public function getSID($dn) {
$domainDN = $this->getDomainDNFromDN($dn);
$cacheKey = 'getSID-'.$domainDN;
if($this->connection->isCached($cacheKey)) {
return $this->connection->getFromCache($cacheKey);
$sid = $this->connection->getFromCache($cacheKey);
if(!is_null($sid)) {
return $sid;
}
$objectSid = $this->readAttribute($domainDN, 'objectsid');

View file

@ -213,30 +213,11 @@ class Connection extends LDAPUtility {
if(is_null($this->cache) || !$this->configuration->ldapCacheTTL) {
return null;
}
if(!$this->isCached($key)) {
return null;
}
$key = $this->getCacheKey($key);
return json_decode(base64_decode($this->cache->get($key)), true);
}
/**
* @param string $key
* @return bool
*/
public function isCached($key) {
if(!$this->configured) {
$this->readConfiguration();
}
if(is_null($this->cache) || !$this->configuration->ldapCacheTTL) {
return false;
}
$key = $this->getCacheKey($key);
return $this->cache->hasKey($key);
}
/**
* @param string $key
* @param mixed $value

View file

@ -297,8 +297,9 @@ class User {
public function getMemberOfGroups() {
$cacheKey = 'getMemberOf'.$this->getUsername();
if($this->connection->isCached($cacheKey)) {
return $this->connection->getFromCache($cacheKey);
$memberOfGroups = $this->connection->getFromCache($cacheKey);
if(!is_null($memberOfGroups)) {
return $memberOfGroups;
}
$groupDNs = $this->access->readAttribute($this->getDN(), 'memberOf');
$this->connection->writeToCache($cacheKey, $groupDNs);

View file

@ -294,10 +294,6 @@ class Test_Group_Ldap extends \Test\TestCase {
$uid = 'someUser';
$gid = 'someGroup';
$cacheKey = 'inGroup'.$uid.':'.$gid;
$access->connection->expects($this->once())
->method('isCached')
->with($cacheKey)
->will($this->returnValue(true));
$access->connection->expects($this->once())
->method('getFromCache')

View file

@ -250,8 +250,9 @@ class USER_LDAP extends BackendUtility implements \OCP\IUserBackend, \OCP\UserIn
* @throws \Exception when connection could not be established
*/
public function userExists($uid) {
if($this->access->connection->isCached('userExists'.$uid)) {
return $this->access->connection->getFromCache('userExists'.$uid);
$userExists = $this->access->connection->getFromCache('userExists'.$uid);
if(!is_null($userExists)) {
return (bool)$userExists;
}
//getting dn, if false the user does not exist. If dn, he may be mapped only, requires more checking.
$user = $this->access->userManager->get($uid);
@ -321,8 +322,9 @@ class USER_LDAP extends BackendUtility implements \OCP\IUserBackend, \OCP\UserIn
}
$cacheKey = 'getHome'.$uid;
if($this->access->connection->isCached($cacheKey)) {
return $this->access->connection->getFromCache($cacheKey);
$path = $this->access->connection->getFromCache($cacheKey);
if(!is_null($path)) {
return $path;
}
$user = $this->access->userManager->get($uid);