php自定义加密解决实现代码_PHP教程

// 说明：PHP 写的加密函数,支持私人密钥

function keyED($txt,$encrypt_key)
{
$encrypt_key = md5($encrypt_key);
$ctr=0;
$tmp = "";
for ($i=0;$i {
if ($ctr==strlen($encrypt_key)) $ctr=0;
$tmp.= substr($txt,$i,1) ^ substr($encrypt_key,$ctr,1);
$ctr++;
}
return $tmp;
}

function encrypt($txt,$key)
{
srand((double)microtime()*1000000);
$encrypt_key = md5(rand(0,32000));
$ctr=0;
$tmp = "";
for ($i=0;$i {
if ($ctr==strlen($encrypt_key)) $ctr=0;
$tmp.= substr($encrypt_key,$ctr,1) . (substr($txt,$i,1) ^ substr($encrypt_key,$ctr,1));
$ctr++;
}
return keyED($tmp,$key);
}

function decrypt($txt,$key)
{
$txt = keyED($txt,$key);
$tmp = "";
for ($i=0;$i {
$md5 = substr($txt,$i,1);
$i++;
$tmp.= (substr($txt,$i,1) ^ $md5);
}
return $tmp;
}

$key = "YITU.org";
$string = "我是加密字符";

// encrypt $string, and store it in $enc_text
$enc_text = encrypt($string,$key);

// decrypt the encrypted text $enc_text, and store it in $dec_text
$dec_text = decrypt($enc_text,$key);

print "加密的 text : $enc_text
";
print "解密的 text : $dec_text
";
?>