fix(user): check session key value before using it

SOPE/GDLContentStore/GCSSessionsFolder.m

@@ -204,7 +204,7 @@ static NSString *sessionsFolderURLString = nil;
   NSArray *attrs;
   NSDictionary *record;
   EOEntity *entity;
-  EOSQLQualifier *qualifier;
+  EOQualifier *qualifier;
 
   record = nil;
 
@@ -217,6 +217,7 @@ static NSString *sessionsFolderURLString = nil;
                                          qualifierFormat:
                                             @"c_id='%@'",
                                           theID];
+
       [qualifier autorelease];
 
       [context beginTransaction];

SoObjects/SOGo/SOGoSession.m

@@ -45,6 +45,11 @@
 
   cache = [SOGoCache sharedCache];
 
+  //We check that the session is base64
+  NSData *decodedData = [[NSData alloc] initWithBase64EncodedString:theSessionKey options:0];
+  if(!decodedData)
+    return value;
+
   key = [NSString stringWithFormat: @"session:%@", theSessionKey];
   value = [cache valueForKey: key];