<?php

/**
 * Simple and secury password hashing class
 * @author Julius Beckmann http://juliusbeckmann.de/
 * @license GPL
 * @package password
 */
class password {
    
	/**
	 * Password Salt
	 * -------------------------------
	 * ---- Change every project! ----
	 * -------------------------------
     * Should NOT be changed wenn hashes have been created!
	 * --> Better no umlauts and check for charset!
	 */
    const SALT = 'GZg;:LMjhugkzf!sdth$%fg&gfj(ug)=ui?gfzj';

	/**
	 * Minimum rehashing interations
	 * <= 0 deactivates
     * Do NOT change when hashes have been generated!
	 */
    const ITERATIONS_MIN = 32;

	/**
     * Creates a MD5 hash from a string
	 * 
	 * @param string $pwd
	 * @return string
	 */
    public static function hash($pwd) {
		
		// Always hash once
		$hash = md5($pwd . self::SALT);
		
		if(self::ITERATIONS_MIN > 0) {
			
			// Set minimum interations
			$iter = self::ITERATIONS_MIN;
			
			// Add variable iterations depending on first hash char.
			$iter += (ord($hash[0]) % self::ITERATIONS_MIN);
			
			// Rehash $iter times
			while($iter-- > 1) {
				$hash = md5($hash . self::SALT);
			}
		}
        return $hash;
    }
    
}

// Example usage
/*
foreach(range('a', 'z') as $char) {
	echo $char, ' => ', password::hash($char), "\n";
}
*/