How to compare two passwords in codeigniter using encryption - codeigniter-3

Question

I stored a password in database using an encryption key, but now, when the user wants to login in the system, how can I compare both passwords? Each time it gives a different encrypted password..
$first_password = $this->input->post('password');
$password=$this->encrypt->encode($first_password);
Here is my model code
public function validate_login($username,$password){
$q = $this->db->where(['username'=>$username,'password'=>$password])
->get('oss_user');
if($q->num_rows()){
return $q->row()->user_id;
}
else{
return FALSE;
}
My question is: how can I compare the user entered password with the password stored in database?

Answer 1

You can not compare encrypted password this way. First you have get record from database using email id, once you find row of same email id then you have to pass encrypted password which is store in database on this function "$this->encrypt->decode($encrypted_password);", so you get back original password from encryption form and then compare it with password given during login session, please see follow code.
public function validate_login($username,$password){
$q = $this->db->where(['username'=>$username])
->get('oss_user');
if($q->num_rows()){
$desc_password = $this->encrypt->decode($q->row()->password);
if($desc_password == $password){
return $q->row()->user_id;
}
else
return FALSE;
}
else{
return FALSE;
}