php常用加密解密功能函数收集

方法一：（尚未测试）

function passport_encrypt($txt, $key = 'www.h2sheji.com') 
{ 
  srand((double)microtime() * 1000000); 
  $encrypt_key = md5(rand(0, 32000)); 
  $ctr = 0; 
  $tmp = ''; 
  for($i = 0;$i < strlen($txt); $i++) { 
  $ctr = $ctr == strlen($encrypt_key) ? 0 : $ctr; 
  $tmp .= $encrypt_key[$ctr].($txt[$i] ^ $encrypt_key[$ctr++]); 
  } 
  return urlencode(base64_encode(passport_key($tmp, $key))); 
} 
function passport_decrypt($txt, $key = 'www.h2sheji.com') 
{ 
  $txt = passport_key(base64_decode(urldecode($txt)), $key); 
  $tmp = ''; 
  for($i = 0;$i < strlen($txt); $i++) { 
  $md5 = $txt[$i]; 
  $tmp .= $txt[++$i] ^ $md5; 
  } 
  return $tmp; 
} 
function passport_key($txt, $encrypt_key) 
{ 
  $encrypt_key = md5($encrypt_key); 
  $ctr = 0; 
  $tmp = ''; 
  for($i = 0; $i < strlen($txt); $i++) { 
  $ctr = $ctr == strlen($encrypt_key) ? 0 : $ctr; 
  $tmp .= $txt[$i] ^ $encrypt_key[$ctr++]; 
  } 
  return $tmp; 
} 

用法：

$txt = "1";
$key = "testkey";
$encrypt = passport_encrypt($txt,$key);
$decrypt = passport_decrypt($encrypt,$key);
echo $encrypt."";
echo $decrypt."";

方法2：简单的对称加密

方法3：