Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
513 views
in Technique[技术] by (71.8m points)

php - Crypt() salt generation and password encryption, well executed?

these are some functions I am using for password encryption and password verification. Was wondering if this is a good way to handle it. I am using the codeigniter framework.

This is the function to 'encrypt' :

function crypt_pass( $input ){
    $salt = substr(sha1(date('r')), rand(0, 17), 22);
    $cost = 10;
    $hash = '$2y$' . $cost . '$' . $salt;

    $pw_and_salt['pw'] = crypt($input, "$hash");
    $pw_and_salt['salt'] = $salt;

    return $pw_and_salt;
}

I store both the password and the salt in my DB. Here is the login function:

function login(){

    $this->db->select('salt');
    $salt = $this->db->get_where('users', array('username' => $this->input->post('username') ) )->row();



    $where = array(
        'username' => $this->input->post('username'),
        'password' => crypt( $this->input->post('password'), '$2y$10$' . $salt->salt),
    );


    $user = $this->db->get_where('users', $where)->first_row();

    if (!$user) {
        return FALSE;
    }else{
        if(!empty($user->activation)){

            return 2;

        }else if($user && empty($user->activation)){
            $this->session->set_userdata('id',$user->id);
            $this->session->set_userdata('username',$user->username);
            $this->session->set_userdata('first_name',$user->first_name);   

            return 1;
        }
    }
}

Am I implementing this the right way? Is this enough security?

VERSION 2 : NOT STORING SALT, EXTRACTING FROM PASSWORD IN DB INSTEAD :

function login(){

    $this->db->select('password');

    $pw = $this->db->get_where('users', array('username' => $this->input->post('username') ) )->row();


    $where = array(
        'username' => $this->input->post('username'),
        'password' => crypt( $this->input->post('password'), $pw->password),
    );

    $user = $this->db->get_where('users', $where)->first_row();

    if (!$user) {

        return FALSE;

    }else{

        if(!empty($user->activation)){

            return 2;

        }else if($user && empty($user->activation)){

            $this->session->set_userdata('id',$user->id);
            $this->session->set_userdata('username',$user->username);
            $this->session->set_userdata('first_name',$user->first_name);   

            return 1;
        }
    }
}
See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

There are some points that can be improved, but first i would recommend to use PHP's new function password_hash(). This function will generate a safe salt and includes it in the resulting hash-value, so you can store it in a single database field. There exists also a compatibility pack for earlier versions.

// Hash a new password for storing in the database.
// The function automatically generates a cryptographically safe salt.
$hashToStoreInDb = password_hash($password, PASSWORD_BCRYPT);

// Check if the hash of the entered login password, matches the stored hash.
// The salt and the cost factor will be extracted from $existingHashFromDb.
$isPasswordCorrect = password_verify($password, $existingHashFromDb);

Some thoughts about your code:

  1. You generate a BCrypt hash with crypt(), so the salt will be part of the resulting hash. There is no need to store it separately.
  2. The generation of the salt can be improved, use the random source of the operating system MCRYPT_DEV_URANDOM.
  3. If you would change the cost factor to 9, the format would become invalid, because crypt expects two digits.

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...