Refactor two-factor authentication logic

Updated two-factor authentication to streamline the time format handling using `time()` instead of `DateTime`, reducing code complexity. Also fixed a potential bug in `MY_Model.php` by checking the query object before accessing `num_rows()`.

application/controllers/Login.php

@@ -134,8 +134,7 @@ class Login extends MY_Controller {
 		for ($i = 1; $i < 7; $i ++){
 			$code .= rand(1,9);
 		}
-		$dateTime = new DateTime();
-		$asString = $dateTime->format('Y-m-d H:i:s');
+		$asString = time();
 		 
 		$this->Users_model->update_record(['twofactorcode' =>$code, 'twofactortime'=>$asString ],$userID);
 		return $code;
@@ -146,7 +145,7 @@ class Login extends MY_Controller {
 		$tmpuserid 	= $this->session->userdata( 'tmpuserid' );
 		$code		= $this->clean_input('code');
 		$hoe		= $this->clean_input('hoe');
-		$user		= $this->Users_model->get([],false,true);
+		$user		= $this->Users_model->get($tmpuserid);
 		if ($hoe == "GOOGLE"){
 			$message = $this->checkTwoFactorGoogle($user, $code);
 		}
@@ -160,9 +159,9 @@ class Login extends MY_Controller {
 
     function checkTwoFactorEmail($user,$code){
 		$message	= false;
-		$now 		= strtotime('-10 minutes');
-		$test 		= strtotime($user->twofactortime);
-		if ($now > strtotime($user->twofactortime) )
+		$now 		= time() - (10 * 60);
+		$test 		= $user->twofactortime;
+		if ($now > $test )
 			$message	= "U heeft te lang gewacht, de code is niet meer geldig.";
 		else
 			if ($user->twofactorcode !== $code) $message	= "Code is incorrect.";

application/core/MY_Model.php

@@ -176,7 +176,7 @@ class MY_Model extends CI_Model{
 
 		if ( $fieldname ) $this->db->select( $fieldname );
 		$query = $this->db->get( $this->tablename . ' AS T1' );
-		if ( $query->num_rows() == 0 ) return FALSE;
+		if ( ! $query || $query->num_rows() == 0 ) return FALSE;
 		
 		if ( $row ){
 			$row = $query->row();