<?php
/**
 * Cobub Razor
 *
 * An open source mobile analytics system
 *
 * PHP versions 5
 *
 * @category  MobileAnalytics
 * @package   CobubRazor
 * @author    Cobub Team <open.cobub@gmail.com>
 * @copyright 2011-2016 NanJing Western Bridge Co.,Ltd.
 * @license   http://www.cobub.com/docs/en:razor:license GPL Version 3
 * @link      http://www.cobub.com
 * @since     Version 0.1
 */

/**
 * PasswordHash Model
 *
 * @category PHP
 * @package  Model
 * @author   Cobub Team <open.cobub@gmail.com>
 * @license  http://www.cobub.com/docs/en:razor:license GPL Version 3
 * @link     http://www.cobub.com
 */
class PasswordHash
{

    var $itoa64;
    var $iteration_count_log2;
    var $portable_hashes;
    var $random_state;

    /**
     * PasswordHash function
     * password hash
     *
     * @param string $iteration_count_log2 iteration count log2
     * @param string $portable_hashes      portable hashes
     *
     * @return void
     */
    function PasswordHash ($iteration_count_log2, $portable_hashes)
    {
        $this->itoa64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
        
        if ($iteration_count_log2 < 4 || $iteration_count_log2 > 31)
            $iteration_count_log2 = 8;
        $this->iteration_count_log2 = $iteration_count_log2;
        
        $this->portable_hashes = $portable_hashes;
        
        $this->random_state = microtime() . getmypid();
    }

    /**
     * get_random_bytes function
     * get random bytes
     *
     * @param int $count count
     *
     * @return string output
     */
    function get_random_bytes ($count)
    {
        $output = '';
        if (($fh = @fopen('/dev/urandom', 'rb'))) {
            $output = fread($fh, $count);
            fclose($fh);
        }
        
        if (strlen($output) < $count) {
            $output = '';
            for ($i = 0; $i < $count; $i += 16) {
                $this->random_state = md5(microtime() . $this->random_state);
                $output .= pack('H*', md5($this->random_state));
            }
            $output = substr($output, 0, $count);
        }
        
        return $output;
    }

    /**
     * encode64 function
     * encode
     *
     * @param int $input input
     * @param int $count count
     *
     * @return string output
     */
    function encode64 ($input, $count)
    {
        $output = '';
        $i = 0;
        do {
            $value = ord($input[$i ++]);
            $output .= $this->itoa64[$value & 0x3f];
            if ($i < $count)
                $value |= ord($input[$i]) << 8;
            $output .= $this->itoa64[($value >> 6) & 0x3f];
            if ($i ++ >= $count)
                break;
            if ($i < $count)
                $value |= ord($input[$i]) << 16;
            $output .= $this->itoa64[($value >> 12) & 0x3f];
            if ($i ++ >= $count)
                break;
            $output .= $this->itoa64[($value >> 18) & 0x3f];
        } while ($i < $count);
        
        return $output;
    }

    /**
     * gensalt_private function
     * gensalt private
     *
     * @param int $input input
     *
     * @return string output
     */
    function gensalt_private ($input)
    {
        $output = '$P$';
        $output .= $this->itoa64[min(
            $this->iteration_count_log2 + ((PHP_VERSION >= '5') ? 5 : 3), 30
        )];
        $output .= $this->encode64($input, 6);
        
        return $output;
    }

    /**
     * crypt_private function
     * crypt private
     *
     * @param string $password password
     * @param string $setting  setting
     *
     * @return string output
     */
    function crypt_private ($password, $setting)
    {
        $output = '*0';
        if (substr($setting, 0, 2) == $output)
            $output = '*1';
        
        if (substr($setting, 0, 3) != '$P$')
            return $output;
        
        $count_log2 = strpos($this->itoa64, $setting[3]);
        if ($count_log2 < 7 || $count_log2 > 30)
            return $output;
        
        $count = 1 << $count_log2;
        
        $salt = substr($setting, 4, 8);
        if (strlen($salt) != 8)
            return $output;
            
            // We're kind of forced to use MD5 here since it's the only
            // cryptographic primitive available in all versions of PHP
            // currently in use. To implement our own low-level crypto
            // in PHP would result in much worse performance and
            // consequently in lower iteration counts and hashes that are
            // quicker to crack (by non-PHP code).
        if (PHP_VERSION >= '5') {
            $hash = md5($salt . $password, true);
            do {
                $hash = md5($hash . $password, true);
            } while (-- $count);
        } else {
            $hash = pack('H*', md5($salt . $password));
            do {
                $hash = pack('H*', md5($hash . $password));
            } while (-- $count);
        }
        
        $output = substr($setting, 0, 12);
        $output .= $this->encode64($hash, 16);
        
        return $output;
    }

    /**
     * gensalt_extended function
     * gensalt extended
     *
     * @param string $input input
     *
     * @return string output
     */
    function gensalt_extended ($input)
    {
        $count_log2 = min($this->iteration_count_log2 + 8, 24);
        // This should be odd to not reveal weak DES keys, and the
        // maximum valid value is (2**24 - 1) which is odd anyway.
        $count = (1 << $count_log2) - 1;
        
        $output = '_';
        $output .= $this->itoa64[$count & 0x3f];
        $output .= $this->itoa64[($count >> 6) & 0x3f];
        $output .= $this->itoa64[($count >> 12) & 0x3f];
        $output .= $this->itoa64[($count >> 18) & 0x3f];
        
        $output .= $this->encode64($input, 3);
        
        return $output;
    }

    /**
     * gensalt_blowfish function
     * gensalt blowfish
     *
     * @param string $input input
     *
     * @return string output
     */
    function gensalt_blowfish ($input)
    {
        // This one needs to use a different order of characters and a
        // different encoding scheme from the one in encode64() above.
        // We care because the last character in our encoded string will
        // only represent 2 bits. While two known implementations of
        // bcrypt will happily accept and correct a salt string which
        // has the 4 unused bits set to non-zero, we do not want to take
        // chances and we also do not want to waste an additional byte
        // of entropy.
        $itoa64 = './ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
        
        $output = '$2a$';
        $output .= chr(ord('0') + $this->iteration_count_log2 / 10);
        $output .= chr(ord('0') + $this->iteration_count_log2 % 10);
        $output .= '$';
        
        $i = 0;
        do {
            $c1 = ord($input[$i ++]);
            $output .= $itoa64[$c1 >> 2];
            $c1 = ($c1 & 0x03) << 4;
            if ($i >= 16) {
                $output .= $itoa64[$c1];
                break;
            }
            
            $c2 = ord($input[$i ++]);
            $c1 |= $c2 >> 4;
            $output .= $itoa64[$c1];
            $c1 = ($c2 & 0x0f) << 2;
            
            $c2 = ord($input[$i ++]);
            $c1 |= $c2 >> 6;
            $output .= $itoa64[$c1];
            $output .= $itoa64[$c2 & 0x3f];
        } while (1);
        
        return $output;
    }

    /**
     * HashPassword function
     * Hash Password
     *
     * @param string $password password
     *
     * @return string md5
     */
    function HashPassword ($password)
    {
        // $random = '';
        
        // if (CRYPT_BLOWFISH == 1 && !$this->portable_hashes) {
        // $random = $this->get_random_bytes(16);
        // $hash =
        // crypt($password, $this->gensalt_blowfish($random));
        // if (strlen($hash) == 60)
        // return $hash;
        // }
        
        // if (CRYPT_EXT_DES == 1 && !$this->portable_hashes) {
        // if (strlen($random) < 3)
        // $random = $this->get_random_bytes(3);
        // $hash =
        // crypt($password, $this->gensalt_extended($random));
        // if (strlen($hash) == 20)
        // return $hash;
        // }
        
        // if (strlen($random) < 6)
        // $random = $this->get_random_bytes(6);
        // $hash =
        // $this->crypt_private($password,
        // $this->gensalt_private($random));
        // if (strlen($hash) == 34)
        // return $hash;
        
        // Returning '*' on error is safe here, but would _not_ be safe
        // in a crypt(3)-like function used _both_ for generating new
        // hashes and for validating passwords against existing hashes.
        return md5($password);
    }
    
    /**
     * CheckPassword function
     * check Password
     *
     * @param string $password    password
     * @param string $stored_hash stored hash
     *
     * @return string md5
     */
    function CheckPassword ($password, $stored_hash)
    {
        // $hash = $this->crypt_private($password, $stored_hash);
        // if ($hash[0] == '*')
        // $hash = crypt($password, $stored_hash);
        $hash = md5($password);
        return $hash == $stored_hash;
    }
}

?>
