<?php
/**
 * Enter description here...
 * 
 * example：
 * <pre>
 * 
 * </pre>
 * 
 * @name Q_Utils_AuthCode
 * @version version (2009-10-22 上午10:45:12)
 * @package Q.Utils.AuthCode
 * @author ziyang liuziyang@360quan.com
 * @since 1.0
 */

class Lib_AuthCode {
	
	/**
	 * 验证编码
	 *
	 * @param String $string
	 * @param String $operation
	 * @param Integer $expiry
	 * @param String $key
	 * @return String
	 */
	private static function auth( $string, $key, $expiry = 0, $operation = 'decode' ) {
		$ckey_length = 4;
		$key = md5($key);
		$keya = md5(substr($key, 0, 16));
		$keyb = md5(substr($key, 16, 16));
		$keyc = $ckey_length ? ($operation == 'decode' ? substr($string, 0, $ckey_length) : substr(md5(microtime()), -$ckey_length)) : '';
		$cryptkey = $keya . md5($keya . $keyc);
		$key_length = strlen($cryptkey);
		$string = $operation == 'decode' ? base64_decode(substr($string, $ckey_length)) : sprintf('%010d', $expiry ? $expiry + time() : 0) . substr(md5($string . $keyb), 0, 16) . $string;
		$string_length = strlen($string);
		
		$result = '';
		$box = range(0, 255);
		
		$rndkey = array();
		for ($i = 0; $i <= 255; $i++) {
			$rndkey[$i] = ord($cryptkey[$i % $key_length]);
		}
		
		for ($j = $i = 0; $i < 256; $i++) {
			$j = ($j + $box[$i] + $rndkey[$i]) % 256;
			$tmp = $box[$i];
			$box[$i] = $box[$j];
			$box[$j] = $tmp;
		}
		
		for ($a = $j = $i = 0; $i < $string_length; $i++) {
			$a = ($a + 1) % 256;
			$j = ($j + $box[$a]) % 256;
			$tmp = $box[$a];
			$box[$a] = $box[$j];
			$box[$j] = $tmp;
			$result .= chr(ord($string[$i]) ^ ($box[($box[$a] + $box[$j]) % 256]));
		}
		
		if ($operation == 'decode') {
			if ((substr($result, 0, 10) == 0 || substr($result, 0, 10) - time() > 0) && substr($result, 10, 16) == substr(md5(substr($result, 26) . $keyb), 0, 16)) {
				return substr($result, 26);
			}
			else {
				return false;
			}
		}
		else {
			return $keyc . str_replace('=', '', base64_encode($result));
		}
	}
	/**
	 * 解密
	 *
	 * @param String $string
	 * @param String $key
	 * @param Integer $expiry
	 * @return String
	 */
	public static function decode( $string, $key, $expiry = 0 ) {
		return self::auth($string, $key, $expiry, __FUNCTION__);
	}
	
	/**
	 * 加密
	 *
	 * @param String $string
	 * @param String $key
	 * @param Integer $expiry
	 * @return String
	 */
	public static function encode( $string, $key, $expiry = 0 ) {
		return self::auth($string, $key, $expiry, __FUNCTION__);
	}
	
	/**
	 * 获取编码
	 *
	 * @param String $plaintext
	 * @param String $salt
	 * @param String $encryption
	 * @param bool $show_encrypt
	 * @return String
	 */
	public static function getCrypted( $plaintext, $salt = '', $encryption = 'md5-hex', $show_encrypt = false ) {
		$salt = self::getSalt($encryption, $salt, $plaintext);
		switch ($encryption) {
			case 'plain' :
				return $plaintext;
			case 'sha' :
				$encrypted = base64_encode(mhash(MHASH_SHA1, $plaintext));
				return ($show_encrypt) ? '{SHA}' . $encrypted : $encrypted;
			case 'crypt' :
			case 'crypt-des' :
			case 'crypt-md5' :
			case 'crypt-blowfish' :
				return ($show_encrypt ? '{crypt}' : '') . crypt($plaintext, $salt);
			case 'md5-base64' :
				$encrypted = base64_encode(mhash(MHASH_MD5, $plaintext));
				return ($show_encrypt) ? '{MD5}' . $encrypted : $encrypted;
			case 'ssha' :
				$encrypted = base64_encode(mhash(MHASH_SHA1, $plaintext . $salt) . $salt);
				return ($show_encrypt) ? '{SSHA}' . $encrypted : $encrypted;
			case 'smd5' :
				$encrypted = base64_encode(mhash(MHASH_MD5, $plaintext . $salt) . $salt);
				return ($show_encrypt) ? '{SMD5}' . $encrypted : $encrypted;
			case 'aprmd5' :
				$length = strlen($plaintext);
				$context = $plaintext . '$apr1$' . $salt;
				$binary = self::_bin(md5($plaintext . $salt . $plaintext));
				for ($i = $length; $i > 0; $i -= 16) {
					$context .= substr($binary, 0, ($i > 16 ? 16 : $i));
				}
				for ($i = $length; $i > 0; $i >>= 1) {
					$context .= ($i & 1) ? chr(0) : $plaintext[0];
				}
				$binary = self::_bin(md5($context));
				
				for ($i = 0; $i < 1000; $i++) {
					$new = ($i & 1) ? $plaintext : substr($binary, 0, 16);
					if ($i % 3) {
						$new .= $salt;
					}
					if ($i % 7) {
						$new .= $plaintext;
					}
					$new .= ($i & 1) ? substr($binary, 0, 16) : $plaintext;
					$binary = self::_bin(md5($new));
				}
				
				$p = array();
				for ($i = 0; $i < 5; $i++) {
					$k = $i + 6;
					$j = $i + 12;
					if ($j == 16) {
						$j = 5;
					}
					$p[] = self::_toAPRMD5((ord($binary[$i]) << 16) | (ord($binary[$k]) << 8) | (ord($binary[$j])), 5);
				}
				
				return '$apr1$' . $salt . '$' . implode('', $p) . self::_toAPRMD5(ord($binary[11]), 3);
			
			case 'md5-hex' :
			
			default :
				$encrypted = ($salt) ? md5($plaintext . $salt) : md5($plaintext);
				return ($show_encrypt) ? '{MD5}' . $encrypted : $encrypted;
		}
	}
	
	/**
	 * Enter description here...
	 *
	 * @param unknown_type $encryption
	 * @param unknown_type $seed
	 * @param unknown_type $plaintext
	 * @return unknown
	 */
	public static function getSalt( $encryption = 'md5-hex', $seed = '', $plaintext = '' ) {
		switch ($encryption) {
			case 'crypt' :
			case 'crypt-des' :
				if ($seed) {
					return substr(preg_replace('|^{crypt}|i', '', $seed), 0, 2);
				}
				else {
					return substr(md5(mt_rand()), 0, 2);
				}
				break;
			
			case 'crypt-md5' :
				if ($seed) {
					return substr(preg_replace('|^{crypt}|i', '', $seed), 0, 12);
				}
				else {
					return '$1$' . substr(md5(mt_rand()), 0, 8) . '$';
				}
				break;
			
			case 'crypt-blowfish' :
				if ($seed) {
					return substr(preg_replace('|^{crypt}|i', '', $seed), 0, 16);
				}
				else {
					return '$2$' . substr(md5(mt_rand()), 0, 12) . '$';
				}
				break;
			
			case 'ssha' :
				if ($seed) {
					return substr(preg_replace('|^{SSHA}|', '', $seed), -20);
				}
				else {
					return mhash_keygen_s2k(MHASH_SHA1, $plaintext, substr(pack('h*', md5(mt_rand())), 0, 8), 4);
				}
				break;
			
			case 'smd5' :
				if ($seed) {
					return substr(preg_replace('|^{SMD5}|', '', $seed), -16);
				}
				else {
					return mhash_keygen_s2k(MHASH_MD5, $plaintext, substr(pack('h*', md5(mt_rand())), 0, 8), 4);
				}
				break;
			
			case 'aprmd5' :
				/* 64 characters that are valid for APRMD5 passwords. */
				$APRMD5 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
				
				if ($seed) {
					return substr(preg_replace('/^\$apr1\$(.{8}).*/', '\\1', $seed), 0, 8);
				}
				else {
					$salt = '';
					for ($i = 0; $i < 8; $i++) {
						$salt .= $APRMD5{rand(0, 63)};
					}
					return $salt;
				}
				break;
			
			default :
				$salt = '';
				if ($seed) {
					$salt = $seed;
				}
				return $salt;
				break;
		}
	}
	
	public static function genRandom( $length = 8 ) {
		$salt = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
		$len = strlen($salt);
		$makepass = '';
		
		$stat = @stat(__FILE__);
		if (empty($stat) || !is_array($stat))
			$stat = array(
				php_uname()
			);
		
		mt_srand(crc32(microtime() . implode('|', $stat)));
		
		for ($i = 0; $i < $length; $i++) {
			$makepass .= $salt[mt_rand(0, $len - 1)];
		}
		
		return $makepass;
	}
	
	public static function _toAPRMD5( $value, $count ) {
		/* 64 characters that are valid for APRMD5 passwords. */
		$APRMD5 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
		$aprmd5 = '';
		$count = abs($count);
		while (--$count) {
			$aprmd5 .= $APRMD5[$value & 0x3f];
			$value >>= 6;
		}
		return $aprmd5;
	}
	
	public static function _bin( $hex ) {
		$bin = '';
		$length = strlen($hex);
		for ($i = 0; $i < $length; $i += 2) {
			$tmp = sscanf(substr($hex, $i, 2), '%x');
			$bin .= chr(array_shift($tmp));
		}
		return $bin;
	}
	
	/**
	 * 组合一个安全的密码
	 * @param $code
	 * @return String
	 */
	public static function makePass( $code ) {
		$salt = self::genRandom(32);
		$crypt = self::getCrypted($code . $salt, $salt);
		return $crypt . ':' . $salt;
	}
	
	/**
	 * 验证密码
	 *
	 * @param String $inputPassword
	 * @param String $password
	 * @return bool
	 */
	public static function authPassword( $inputPassword, $password ) {
		if (empty($password) || empty($inputPassword)) {
			return false;
		}
		$passwordList = explode(':', trim($password));
		if (count($passwordList) != 2) {
			return false;
		}
		list($crypt, $salt) = $passwordList;
		$decode = self::getCrypted($inputPassword . $salt, $salt);
		if ($crypt != $decode) {
			return false;
		}
		return true;
	}
}