functions used to encrypt password in php?

Question

I am programming a PHP site that allows users to register,I\'m using codeigniter php and I want to know the best function to encrypt passwords and what difference between this f

Answer 1

Passwords should almost never be encrypted. Instead, they should be one-way hashed.

Generally, bcrypt is recommended, as it's resistant to brute forcing, where common alternatives like md5 or sha1 fail.

Answer 2

Use PHPass: http://www.openwall.com/phpass/

The preferred (most secure) hashing method supported by phpass is the OpenBSD-style Blowfish-based bcrypt, also supported with our public domain crypt_blowfish package (for C applications), and known in PHP as CRYPT_BLOWFISH, with a fallback to BSDI-style extended DES-based hashes, known in PHP as CRYPT_EXT_DES, and a last resort fallback to MD5-based salted and variable iteration count password hashes implemented in phpass itself (also referred to as portable hashes).

Put it in application/third_party, and use vanilla PHP to load it (not CI's loader):

require_once APPPATH.'third_party/phpass-0.3/PasswordHash.php';
$hash_iterations = 100;
$portable_hashes = FALSE;
$phpass = new PasswordHash($hash_iterations, $portable_hashes);

Example usage:

// Hash a password before storing it in the DB
$hashed_password = $phpass->HashPassword($user_input);

// Check a given password against a stored hashed password
$is_valid = $phpass->CheckPassword($user_input, $stored_hash_of_password);

Answer 3

This is a custom encryption class which im using in codeigniter

<?php
class Encryption {
    var $skey   = "EsUriEncKey2012"; 

    public  function safe_b64encode($string) {

        $data = base64_encode($string);
        $data = str_replace(array('+','/','='),array('-','_',''),$data);
        return $data;
    }

    public function safe_b64decode($string) {
        $data = str_replace(array('-','_'),array('+','/'),$string);
        $mod4 = strlen($data) % 4;
        if ($mod4) {
            $data .= substr('====', $mod4);
        }
        return base64_decode($data);
    }

    public  function encode($value){ 

        if(!$value){return false;}
        $text = $value;
        $iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
        $iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
        $crypttext = mcrypt_encrypt(MCRYPT_RIJNDAEL_256, $this->skey, $text, MCRYPT_MODE_ECB, $iv);
        return trim($this->safe_b64encode($crypttext)); 
    }

    public function decode($value){

        if(!$value){return false;}
        $crypttext = $this->safe_b64decode($value); 
        $iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_256, MCRYPT_MODE_ECB);
        $iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
        $decrypttext = mcrypt_decrypt(MCRYPT_RIJNDAEL_256, $this->skey, $crypttext, MCRYPT_MODE_ECB, $iv);
        return trim($decrypttext);
    }
}
?>